
Glass C> A 

Book, 6 ' 



U. S. DEPARTMENT OF AGRICULTURE, 
BUREAU OF ENTOMOLOGY— BULLETIN No. 103. 

L. O. HOWARD, Entomologist and Chief of Bureau. 



THE PLUM CURCULIO. 



, A. L. QUAINTANCE, 

In Charge of Deciduous Fruit Insect Investigations, 

AND 

E. L. JENNE, 

Agent and Expert, Deciduous Fruit Insect Investigations. 



Issued July 13, 1912. 




WASHINGTON": 

GOVERNMENT PRINTING OFFICE. 

1912. 



T* 



Monograph 



Bui. 1 03> Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate 




Stages and Work of the Plum Curculio. 

Fig. 1, The adult or beetle, lateral aspect; fig. 2, beetle, dorsal aspect; fig. 3, larva, or grub, 
lateral aspect ; fig. 4, pupa, ventral aspect ; fig. 5, larva, and its work in cherry ; fig. 6, injury 
to ripe peach; fig. 7, feeding punctures and scars from egg punctures on apple. Figs. 1-4, 
enlarged about 8 times; Figs. 5-7, natural size. (Original.) 



U. S. DEPARTMENT OF AGRICULTURE, 

BUREAU OF ENTOMOLOGY— BULLETIN No. 103. 

L. O. HOWARD, Entomologist and Chief of Bureau. 



THE PLUM CURCULIO 



A. L. QUAINTANCE, 

In Charge of Deciduous Fruit Insect Investigations, 

AND 

E. L. JENNE, 

Agent and Expert, Deciduous Fruit Insect Investigations. 



Issued July 13, 1912. 




WASHINGTON": 

GOVERNMENT PRINTING OFFICE. 

1912. 










BUREAU OF ENTOMOLOGY. 

L. 0. Howard, Entomologist and Chief of Bureau. 
C. L. Maelatt, Entomologist and Acting Chief in Absence of Chief . 
R. S. Clifton, Executive Assistant. 
W. F. Tastet, Chief Clerk. 

F. H. Chittenden, in charge of truck crop and stored product insect investigations. 

A. D. Hopkins, in charge of forest insect investigations. 

W. D. Hunter, in charge of southern field crop insect investigations. 

F. M. Webster, in charge of cereal and forage insect investigations. 

A. L. Quaintance, in charge of deciduous fruit insect investigations. 

E. F. Phillips, in charge of bee culture. 

D. M. Rogers, in charge of preventing spread of moths , field work. 

Rolla P. Currie, in charge of editorial work. 

Mabel Colcord, in charge of library. 

Deciduous Fruit Insect Investigations. 

A. L. Quaintance, in charge. 

Fred Johnson, E. L. Jenne, S. W. Foster, P. R. Jones, F. E. Brooks, A. G. 
Hammar, E. W. Scott, R. L. Nougaret, R. A. Cushman, L. L. Scott, J. B. 
Gill, A. C. Baker, W. M. Davidson, E. B. Blakeslee, W. B.Wood, E. H. 
Siegler, F. L. Simanton, entomological assistants. 

J. F. Zimmer, N. S. Abbott, W. H. Sill, entomological assistants, employed in enforce- 
ment of insecticide act, 1910. 
2 



LETTER OF TRANSMITTAL. 



U. S. Department of Agriculture, 

Bureau of Entomology, 
Washington, D. C, October 24, 1911. 
Sir: I have the honor to transmit herewith for publication a full 
account of the plum curculio. This is a native insect, and from the 
earliest times has ravaged the plums, peaches, and other deciduous 
fruits grown around the home and in large commercial orchards. 
The total annual loss occasioned by this pest by reason of its attacks 
upon its several food plants amounts to several million dollars, and 
until recently there has been no very practical method of controlling it. 
The plum curculio has been under careful investigation by this 
bureau during the past several years, and, although it has been the 
subject of many papers by entomologists and others, it has not here- 
tofore received the painstaking investigation which its importance 
demands. The present paper is an important contribution to our 
knowledge of the insect, and points out the remedial measures to be 
employed in its control. 

I recommend the publication of this manuscript as Bulletin No. 103 
of this bureau. 

Respectfully, L. O. Howard, 

Entomologist and Chief of Bureau. 
Hon. James Wilson, 

Secretary of Agriculture. 

3 



PREFACE. 



The present bulletin gives results of studies of the plum curculio 
that, with considerable interruption, have been in progress since the 
spring of 1905. The work has been done for the most part in con- 
junction with other investigations at the field laboratories in Decid- 
uous Fruit Insect Investigations, Bureau of Entomology, located in 
important fruit-growing sections and representing a considerable 
range of climatic and other conditions. Data have thus been ob- 
tained on the biology" of the insect in northern, central, and southern 
localities in its range of distribution, as in western New York and 
northwestern Pennsylvania, in the environs of Washington, D. C, and 
in Georgia. Studies for one season were made in the Ozark region of 
Arkansas, well toward its limit of occurrence to the southwest. The 
"observations presented, therefore, fairly well cover the distribution of 
the species, though for the respective localities the results are not 
entirely comparable, as for one reason or another it was found imprac- 
tical for the several workers to carry out uniformly the outline of 
studies originally prepared. 

In the case of but few native American insects are there earlier or 
more complete records of depredations than is true of the plum cur- 
culio. From the time of its first noted injuries, about 175 years ago, 
until the present day this insect has been execrated by commercial 
and amateur fruit growers alike. If we are to judge from the writings 
in the earlier horticultural and agricultural papers, it was especially 
despised by the early settlers for its destruction of choice varieties 
of plums and other stone fruits grown around their homes, and the 
number of remedies proposed was legion. Many workers have con- 
tributed to our present knowledge of the plum curculio, and their 
writings have been freely used in the present paper. Among these may 
be mentioned Fitch, Walsh, Riley, Trimble, Forbes, Howard, Weed, 
Stedman, Crandall, and others. 

Several members of the force engaged in Deciduous Fruit Insect 
Investigations have made important contributions to this report, as 
later credited in the text. Mr. James H. Beattie spent a part of the 
season of 1905 in Georgia, and Mr. A. A. Girault during the same year 
was engaged in life-history observations in the insectary at Washing- 
ton. During 1906 Mr. Girault, with Mr. A. H. Rosenfeld, spent the 
season in Georgia working on the curculio and other peach insects, 
and the year following the former gentleman made observations on this 
insect in southern Ohio. Mr. Girault's careful studies have been of 
the greatest value. During 1905 Mr. Fred Johnson gave considerable 



6 THE PLUM CURCULIO. 

attention to life-history studies of the curculio in western New York, 
as also the year following in northwestern Pennsylvania, in addition 
to numerous field experiments in spraying during these and subse- 
quent years. During 1908 Mr. S. W. Foster and the junior author car- 
ried out extensive life-history investigations and field experiments in 
northwestern Arkansas, and similar work was accomplished the same 
season in the environs of Washington, D. C, by Mr. P. R. Jones. Dur- 
ing 1909 work on the curculio was limited largely to experiments with 
sprays in orchards, made in conjunction with experiments against the 
codling moth, and carried out in Arkansas and Missouri by the junior 
author and Mr. F. W. Faurot, in Virginia by Messrs. J. F. Zimmer and 
E. W. Scott, and in Michigan by Mr. R. W. Braucher. In 1910 impor- 
tant life-history observations were made in Michigan by Mr. A. G. 
Hammar, and many additional data on the curculio in the South were 
obtained during the same year by the junior author and Mr. E. W. 
Scott, with headquarters at Barnesville, Ga. In much of the orchard- 
spraying experiments on both peach and apple the work has been 
done in cooperation with Mr. W. M. Scott, of the Bureau of Plant 
Industry of this department. 

Several publications on the plum curculio have been issued during 
the course of the work. An article on this insect was published in 
the Yearbook of the department for 1905 in a paper entitled "The 
principal insect enemies of the peach." Circular 73 of the Bureau of 
Entomology, on the plum curculio, by Messrs. Fred Johnson and 
A. A. Girault, was published in 1906; and the results of a comparison 
of the demonstration and one-spray methods in the control of the 
codling moth and plum curculio were published in November, 1910, as 
Part VII of Bulletin No. 80 of the Bureau of Entomology, a revised 
edition of which was issued March 30, 1911. Circular 120 of the 
Bureau of Entomology, entitled "Control of the Brown-rot and Plum 
Curculio on Peaches," by W. M. Scott, of the Bureau of Plant Indus- 
try, and the senior author, was issued in March, 1910. This gave 
instructions for the preparation and use of a combined spray for the 
curculio and fungous diseases of the fruit of the peach. The results 
of further experiments in peach spraying for the curculio, brown-rot, 
and scab were given in Farmers' Bulletin 440, by W. M. Scott and 
the senior author, published in March, 1911. 

In the present paper are brought together the more detailed 
results of the studies of this insect which have been in progress, 
including some of the data which have been already published. 
Especial attention has been given to presenting the data as far as 
possible in tabular form, with necessary discussion of the tables to 
bring out the more important points. 

A. L. QuAINTANCE, 

In Charge of Deciduous Fruit Insect Investigations. 



CONTENTS. 



Page. 

Classification and synonymy 13 

Common names 14 

History 15 

Distribution 19 

Western limit of occurrence 21 

Northern limit of occurrence 24 

Southern limit of occurrence 25 

Distribution of the curculio according to life zones 25 

Reported introductions of the curculio 26 

Losses due to the plum curculio 27 

Insects likely to be mistaken for the plum curculio. 28 

Description 30 

The egg 30 

The larva 30 

The pupa 32 

The adult 33 

Food plants 33 

Fruits in which the larvae fail to mature 38 

Life history and habits 39 

The egg 39 

Number of eggs deposited 39 

Length of egg stage 48 

The larva 54 

Habits of larvae just hatched and course taken in fruit 54 

Larval instars 55 

Death of larvae in fruit [ 56 

Desertion of fruit by undersized larvae 59 

Normal emergence of larvae from fruit during the season 60 

Manner of leaving the fruit and entering soil 64 

Time spent in the fruit (egg and larval stages combined) 65 

The pupa. ., 73 

Length of time spent in the soil 73 

Length of pupal stage, and time spent in soil before and after pupation . 83 

Depth of pupal cell 87 

Soil conditions affecting transformations of the curculio in the ground . . 88 

The adult 92 

Period of emergence of beetles 92 

Proportion of sexes 

Choice of food by curculio 96 

Extent of feeding of the respective sexes 98 

Operation of egg laying 99 

Egg and feeding punctures: Position on fruit and variation in form . . . 103 

Relative number of feeding and egg punctures. 106 

Activity of the beetles in egg laying and feeding, by day and by night . . 107 

Time required for transformation from egg to adult 110 

7 



S THE PLUM CURCULIO. 

Page. 
Seasonal history ' 112 

Time of appearance of beetles in spring 112 

Relation of temperature to appearance of beetles 118 

Occurrence of beetles in orchards 120 

Number of generations annually . 125 

Beetles from emergence to hibernation 127 

Hibernation 129 

Mortality of the curculio during hibernation 132 

Percentage of fruit punctured or infested by the plum curculio 134 

Natural enemies 139 

Parasitic insects 140 

(Anaphes) Anaphoidea conotracheli Girault 140 

(Sigalphus) Triaspis curculionis Fitch 142 

(Sigalphus) Triaspis curculionis var. rufus Riley 146 

(Porizon) Thersilochus conotracheli Riley 147 

(Bracon) Microbracon mellitor Say 148 

Bracon dorsata Say 148 

Other hymenopterous parasites : 148 

Myiophasia senea Wiedemann 149 

Cholomyia insequipes Bigot 150 

Pegomya fusciceps Zett 151 

Predaceous insects 152 

Fowls and birds as curculio destroyers 154 

Remedial measures 155 

Historical 155 

Premiums for remedies for the curculio 167 

The Ransom chip process 168 

Jarring for the curculio 168 

Present status of jarring 172 

Cultivation for destruction of pupae 176 

Spraying with arsenicals 178 

Feeding experiments with poisons 185 

Spraying for the curculio on apple 189 

Early experiments 189 

Experiments by the Bureau of Entomology 193 

Experiments at Anderson, Mo 193 

Experiments in western New York and northwestern Pennsylvania . 195 

Experiments at Siloam Springs, Ark 196 

Experiments in Virginia 197 

Experiments at St. Joseph, Mo 198 

Conclusions 200 

Scheme for spraying apple orchards 201 

Spraying peaches with arsenicals 202 

Some results of spraying peaches for the curculio 208 

Directions for the preparation of self-boiled lime-sulphur wash 212 

Directions for using arsenate of lead 213 

Schedule of applications 214 

Midseason varieties 214 

Late varieties 214 

Early varieties 214 

Spraying plums and cherries 215 

Some results of spraying plums 216 

Results of spraying cherries 218 

Ecouomic bibliography 219 

Index 243 



ILLUSTRATIONS. 



PLATES. 

Page. 

Plate I. Stages and work of the plum curculio. Fig. 1.— The adult or beetle, 

lateral aspect. Fig. 2.— Beetle, dorsal aspect. Fig. 3. — Larva. 

Fig. 4. — Pupa. Fig. 5. — Larva, or grub, and its work in cherry. 

Fig. 6.— Injury to ripe peach. Fig. 7.— Feeding punctures and 

scars from egg punctures on apple Frontispiece. 

II. Work of plum curculio on plum. Fig. 1.— Egg and feeding punctures 
on young wild-gOose plum. Fig. 2. — Nearly ripe wild plums, 
showing egg scars and gum exudation from feeding punctures 32 

III. Work of plum curculio on plum. Fig. 1. — Effect of egg and feeding 

punctures, with gum exudations, on ripe Japanese plums. Fig. 2. — 

Fall feeding punctures on ripe prunes 32 

IV. Work of plum curculio on peach. Fig. 1. — The adult curculio on 

newly set peach. Fig. 2. — Curculio larva, or grub, and its work 

in ripe peach 36 

V. Work of plum curculio on peach. Fig. 1. — Wormy windfall peaches. 

Fig. 2. — Peaches deformed by egg and feeding punctures 36 

"VI. Work of plum curculio on peach. Fig. 1. — Deformed ripe peaches. 

Fig. 2. — -Gum exudation from curculio punctures 36 

VII. Work of plum curculio on apple. Fig. 1. — Egg and feeding punctures 

on young apples. Fig. 2. — Egg punctures on apple some days old . . 40 
VIII. Work of plum curculio on apple. Fig. 1. — Young apples, showing 
scars from egg punctures. Fig. 2. — Ripe apples deformed and 

knotty from egg and feeding punctures of the curculio 40 

IX. Work of plum curculio on apple. Fig. 1. — Imperfectly developed 
apple from tree in which curculio grubs matured. Fig. 2. — Small 
drop apples in which curculio grubs matured. Fig. 3. — Nearly 
ripe summer apple from ground, showing extent of feeding by two 

curculio larvae 40 

X. Injury by plum curculio to pears. Knotty and deformed ripe pears 

resulting from egg and feeding punctures 44 

Xl.^Plum curculio injury to cherries. Cherries cut open, showing the 

grub and its work 44 

XII. Methods of study in plum-curculio investigation, Barnesville, Ga. 
Fig. 1. — Out-of-door house used in life-history work. Fig. 2. — Soil 
cages used in obtaining data on life of insect in ground 48 

XIII. The fall feeding punctures of the plum curculio on apple. Fig. 1. — 

Characteristic holes eaten into apple by the beetles in the fall. 

Fig. 2. — Feeding punctures of beetles on summer apples 128 

XIV. Jarring apparatus in use or recently in use against the plum curculio. 

Fig. 1. — A wheelbarrow curculio catcher used in New York State. 
Fig. 2. — Curculio catcher made by sheets on frames, in use a few 

years ago in Georgia 172 

9 



10 THE PLUM CUECULIO. 

Page. 
Plate XV. Benefits of spraying apples for the plum curculio. Fig. 1. — 
Duchess apples from trees in unsprayed plat. Fig. 2. — Duchess 
apples from trees in plat sprayed against the plum curculio with 

arsenate of lead 196 

XVI. Conditions favoring the plum curculio. Fig. 1. — Native plum 
thicket in the south, adjacent to peach orchard. Fig. 2. — Woods 
and thicket adjacent to plum orchard, furnishing the beetles 

with excellent hibernation quarters 200 

XVII. Effect of arsenical sprays on peach foilage, Arlington Farm, Va. 
Fig. 1. — Unsprayed or check tree. Fig. 2. — Tree sprayed once 
with commercial arsenate of lead. Fig. 3. — Tree sprayed once 
with homemade arsenate of lead. Fig. 4. — Tree sprayed once 
with Paris green. Fig. 5. — Tree sprayed once with green arse- 

noid. Fig. 6.— Tree sprayed once with arsenic sulphid 208 

XVI II. Arsenical injury to fruit. Fig. 1. — Elberta peach sprayed three 
times with arsenate of lead, showing burning and cracking effect 
of the poison. Fig. 2. — Japanese plums, showing burning from 

one application of arsenate of lead 208 

XIX. Field experiments in Georgia for control of plum curculio and 
peach diseases. Fig. 1. — Gasoline power outfit in operation. 
Fig. 2. — Determining results of spraying, each peach being cut 

open 212 

XX. Size of peaches at time of first spraying with arsenate of lead, show- 
ing on the left the earliest and on the right the latest stages in 
development when this treatment should be given 214 

TEXT FIGURES. 

Fig. 1. Herbst's figure of plum curculio, accompanying the original descrip- 
tion in 1797 16 

2. An early illustration of the plum curculio, frequently used between 

about 1830 and 1850 17 

3. Peck's figure of the plum curculio, published with his description 

(Rhynchsenus cerasi) in 1819 17 

4. Map showing by the shaded area the distribution of the plum curculio. . 25 

5. The apple curculio (Anthonomus quadrigibbus) 28 

6. The plum gouger (Anthonomus scutellaris) 28 

7. The acorn weevil (Balaninus victoriensis) 29 

8. Fuller's rose beetle (Pantomorus fulleri) 29 

9. Imbricated snout beetle (Epicxrus imbricatus) 29 

10. The plum curculio ( Conotrachelus nenuphar) : Egg 30 

11. The plum curculio: Larva, showing structural details 30 

12. The plum curculio: Head of larva, with parts named 31 

13. The plum curculio: Head of larva, lateral aspect, with parts named.. 31 

14. The plum curculio: Head of larva, ventral aspect, with parts named. . 31 

15. The plum curculio: Lateral, dorsal, and ventral aspects of right man- 

dible of larva, with muscles 31 

16. The plum curculio: Dorsal aspect of maxilla and labium of larva, with 

parts named 32 

17. The plum curculio: Pupa, showing structural details 32 

18. The plum curculio: Mouth parts of the adult 33 

19. Black-knot of plum, showing, on the left, infestation by plum- 

curculio larvae 37 



• ILLUSTRATIONS. 11 

Page. 
Fig. 20. Diagram showing normal emergence from fruit of larvae of plum cur- 
culip during season at Siloam Springs, Ark., Barnesville, Ga., Wash- 
ington, D. C, and Douglas, Mich 61 

21. Diagram showing normal emergence from soil of beetles of the plum 

curculio for the season at Barnesville, Ga 94 

22. Diagram showing normal emergence from soil of beetles of the plum 

curculio for the season at Siloam Springs, Ark 94 

23. The normal plum-curculio egg puncture and egg 105 

24. Diagram of portion of peach orchard used in jarring experiments against 

the plum curculio, Barnesville, Ga., 1910 122 

25. (Anaphes) Anaphoidea conotracheli, an egg parasite of the plum cur- 

culio 140 

26. (Sigalphus) Triaspis curculionis, an important parasite of the plum 

curculio 142 

27. (Porizon) Thersilochus conotracheli, parasitic upon the plum curculio . 147 

28. (Bracori) Microbracon mellitor, an occasional parasite of the plum cur- 

culio t 148 

29. Myiophasia senea, a dipterous plum-curculio parasite: Male and head 

of female 149 

30. Cholomyia ineequipes, a fly reared abundantly from the plum cur- 

culio at Barnesville, Ga.: Adult, puparium in curculio larval skin. 151 

31. Chrysopa oculata 153 

32. Marpalus pennsylvanicus, a ground beetle predatory upon the plum 

curculio 153 

33. Chauliognathus pennsylvanicus 154 

34. A simple form of curculio catcher for use by one person 170 

35. A cumbersome wheelbarrow type of curculio catcher developed and 

patented about 1869 171 

36. A light wheelbarrow curculio catcher for sale as late as 1905 171 



THE PLUM CURCULIO. 



CLASSIFICATION AND SYNONYMY. 

The Rhynchophora, or snout beetles, to which suborder the plum 
curculio belongs, constitute a very large and important group of 
coleopterous insects, comprising some of our worst insect pests, as 
the cotton-boll weevil, grain and rice weevils, nut weevils, plum 
gouger, strawberry weevil, etc. 

The genus Conotrachelus is distinctly American. Le Conte and 
Horn, in the Rhynchophora of North America, published in 1876, 
list for this genus 26 species from America north of Mexico. There 
are, however, many representatives of the genus, the species being 
especially abundant in the Tropics. Champion, in Volume IV, part 4, 
of the Coleoptera of the Biologia Centrali Americana, has listed 188 
species, and states that about 200 have been described (1906). 

The plum curculio was first characterized and named in 1797 by 
Herbst in his "Natursystem aller bekannten in- und auslandischen 
Insekten-Kaf er " and figured under the name Curculio nenuphar, 
the original description being as follows: 1 

587. Curculio Nenuphar. 

ZTeun unb neunjigfte CCctfef. ^tg. 8. H. 

Mus. Herschel. Cure, longirostris fusco griseoque variegatus, inaequalis, thorace 
punctis duobus elevatis nigris, elytris lineis elevatis interruptis, dorso gibber cari- 
natus. 

2)er Kafer ift of)ngefai)r brittefialb £inien lang, braun unb grei§fd)ecfig, bte (Dberpdje 
fefyr uneben. Det Hiiffel ift fctft langer, al§ ber Britftfcfyiib, gtemlicb bid* , runb, gefriinrat 
braun unb gretSfdjetftg, am (£nbe fdjtoarj, auf bent Hiicfen eine feine erfyo&ete £inie. Die 

1 From the collection Herschel. A. long-snouted curculio, varied with brown and gray, unequal; thorax 
with two elevated black punctures, the elytra with elevated, interrupted lines; the back gibbous and 
carinate. 

The beetle is about 3£ lines long, varied with brown and gray, the surface very uneven. The beak is 
almost longer than the thorax, moderately thick, round, curved, varied with brown and gray, black at 
tip, on the upper side with a fine elevated line. The eyes are black and are not prominent; the antennae 
are brown. The thorax is varied with brown and gray, on the dorsal surface a very fine, elevated line, 
on each side of which is anteriorly a large, elevated black dot, and a smaller one posteriorly; these smaller 
ones a little closer to the median line. The scutellum is depressed. The elytra are varied with brown and 
gray and possess elevated and always interrupted lines; some of these are more elevated, others less, 
one at the middle near the suture is much more strongly elevated than the others and forms a large, black, 
elevated, acutely cariniform tubercle; more toward the tip but also near the suture is again a strongly 
elevated, abrupt line, the second in size but not equal to that on the dorsum. The legs are also varied 
with brown and gray, the coxae are two-toothed. 

The home is North America, 

13 



14 THE PLUM CURCULIO. 

2Iugen ftnb fctytrmrs, unb ftetyen nicf»t toor; bie ^iityttyorner ftnb braun. Der Bruftfctyitb 
ift 'braun unb gretSfdjecfig, ouf bent Hiicfen ift cine fetyr feine ertyotyete £inie, an jeber 
Seite berfelben'ftetyt nacty borne gu em grower ertyotyeter fdjttmrjer puntt,unb ein ffeinerer 
nacty tyinten jit, bie fteineren ftetyen ettt>a§ bitter an ber tnitteHtnie. Da§ SctyitMein liegt 
tief. Die Decf fdjitbe ftnb braun unb grei§fd)ecfig, unb tyaben ertyotyete ftet§ abgebroctyene 
£inien,einige ertyotyen fid) metyr, anbre toeniger, eine auf ber IHitte neben ber Hatty ertyotyet 
fid) toeit ftarier, al§ bie iibrigen, unb ttrirb ein grower fctytoarger, langlicfjer, fctyarf, fiel* 
forntig ertyotyeter Bocfer; metyr nacty ber Spitje ju aucty neben ber Hatty ftetyt trneber eine 
ftarf ertyotyete abgebrodjene £inie, bie gtoetyte am Hang, aber nictyt ber auf bent Hiicfen 
gteicty. Pie ^iijge finb aud) braun unb grei§fctyecfig, bie ^iiften gu>et)ntal gebornt. 
Da§ Datertanb ift Horbanterifa. 

In 1802 the insect was redescribed by Fabricius in Systema Eleu- 
theratorum under the name Rhynchsenus argula; in his catalogue of 
the Insects of Pennsylvania, published in 1806, Rev. F. V. Mel- 
sheimer used for the plum curculio the name Curculio persicx; and in 
1819 Peck in the Massachusetts Agricultural Repository and 
Journal named the species Rhynchxnus cerasi. Dejean lists the cur- 
culio in his Catalogue des Coleopteres, published in 1833, as Cono- 
trachelus variegatus, and in Sturm's Catalogue (1843) it is given as 
Conotrachelus gibhosus Melsheimer. 

The generic position of the insect has been changed from time to 
time according to the ideas of different writers. Our species appears 
first to have been referred to Conotrachelus in 1837 by Schoenherr 
in his Genera et Species Curculionidum under Fabricius's name 
argula. This genus, accredited by some writers to Latreille, was 
fully characterized by Schoenherr, who is cited by Le Conte and Horn 
and by other systematists as author of the genus. In Say's Ento- 
mology of North America, published in 1831, the name Crypto- 
rhyncus argula is used. 

The present synonymy of the species is therefore as follows : 

1797. Curculio nenuphar Herbst, Kafer, Natursystem aller Insekten, VII, p. 29, Tafeln, 

99, f. 8, H. 
1801. Rhynchsenus argula Fabricius, Systema Eleutheratorum, II, p. 467. 
1806. Curculio persicse Melsheimer, Catalogue of the Insects of Pennsylvania (No. 

589), p. 28. 
1819. Rhynchxnus cerasi Peck, Mass. Agric. Repos. and Journ., V, p. 312. 
1831. Chryptorhynchus argula Say (Descr. N. Am. Curculionides), Ent. North America,, 

I, p. 285 (1859). 
1833. Conotrachelus variegatus Dejean, Cat. des Coleopteres, 2d ed., p. 297; 3d ed., p. 

321; lists as variegatus. 
1843. Conotrachelus gibbosus Melsheimer, Sturm's Catalogue, p. 222. 

COMMON NAMES. 

The plum curculio has been referred to in literature under many 
common names, as the fruit curculio, curculio, cherry weevil, peach 
weevil, peach curculio, peach worm, plum curculio, nenuphar, little 
Turk, Turk, kerkelo, little joker, etc. Simply " curculio" or " fruit 
curculio " was employed in many of the earlier articles, though "plum 
weevil" is also frequently to be noted. The word curculio is of 



HISTORY. 15 

Latin origin. It was used by Cato in De Re Rustica (p. 92), 201 B. C, 
and other writings; also by Palladius, A. D. 210; by Pliny; and by 
other Roman authors. It is the name of a well-known comedy of 
Plautus. In its Latin signification the curculio means a cornworm 
or weevil, and probably for this reason the name was adopted by 
Linnaeus in his Systema Naturae, as the genus for a large and di- 
verse assemblage of species of snout beetles. While the Linnsean 
genus Curculio has long since fallen into disuse by entomologists, the 
various species having been distributed into other genera, the word 
is retained in the English vocabulary and applied with qualifying 
adjectives as the common names of several species of snout beetles, 
e. g., the plum curculio, rhubarb curculio, poplar curculio, willow 
curculio, etc. As between the numerous common names applied to 
the insect under consideration, plum curculio has perhaps become 
most firmly established from frequent use in the economic literature 
of the past 20 or 25 years, and the name has recently been adopted 
by the American Association of Economic Entomologists. It is 
nevertheless misleading since, while partial to plums, the curculio 
also injures numerous other fruits. In fact its omnivorous habits 
as regards stone and pome fruits make it unique among a group 
of weevils which as a rule confine themselves to one or but few food 
plants. 

HISTORY. 

Few American insects have been more written about than the 
plum curculio. The earliest statement referring to this insect which 
we have seen is in a letter from Peter Collinson to John Bartram, 
evidently in response to a complaint by Bartram in an earlier com- 
munication. Under date of February 3, 1736, Collinson wrote: "I 
never heard it was insects that annoyed your plums, apricots, and nec- 
tarines. If they are, water that has tobacco leaves soaked in it will 
kill them by making a basin around the trees, watering them fre- 
quently with the water." This reference considered alone might 
appear to refer to the peach-tree borer. Subsequent correspond- 
ence, however, between Bartram and Collinson, cited under history 
of remedies (p. 156), indicates that probably the curculio was the 
insect referred to. There are, later, undoubted references to this 
insect in the correspondence between these two gentlemen, which are 
quoted on page 156. It would appear that the curculio had become 
quite troublesome, at least in the environs of Philadelphia, before 
1750. 

A note by the Swedish naturalist, Peter Kalm, under date of May 
18, 1749, and quoted in the bibliography, leaves no doubt of the 
prevalence of the species in the territory about which he was writing^ 
namely, New Jersey. The original description of this species by 
Herbst in 1797 indicates that by that time the insect had found its 



16 THE PLUM CURCULIO. 

way into European collections. Benjamin Smith Barton, writing 
in 1802, states: "The unripe fruit of the peach is greatly injured by 
the curculio, but the insects most pernicious to the trees are two 
lepidopterous insects of the genus Zygsena of Fabricius. These, 
while in the larval state, destroy the bark of the root." 

An extended account of the curculio by Dr. James Tilton was 
published in Willisch's Domestic Encyclopaedia in 1804. A con- 
siderable knowledge of the insect is shown at this early period and 
the article was much quoted by subsequent writers for several years. 
With the increase in the number of journals and papers devoted to 
horticulture and agriculture, references to the curculio were much 
more frequent. During the first 30 years of the nineteenth century 
numerous short articles and notes appeared, the following being 
among the more important contributors: Dr. James Tilton, J. E. 
Muse, James Thacher, S. L. Mitchell, William Prince, William 




Fig. 1. — Herbst's figure of the plum curculio; accompanying the original description in 1797. 

Wilson, and W. D. Peck. (See figs. 1 and 2 for early illustrations 
of the plum curculio.) 

Beginning about 1830 there was a noticeable increase in the number 
of references and articles relating to this pest from practical fruit 
growers and others, giving their experience in the use of remedies 
and suggesting plans for circumventing its injuries. Some of the 
more important writers between 1830 and 1850 were David Thomas, 
S. Reynolds, R. P. Hildreth, William Wilson, B. Manley, Dr. Joel 
Burnett, John Parsons, A. J. Downing, James Matthews, C. E. 
Goodrich, and there were many others. 

Excepting Melsheimer (see bibliography), the plum curculio ap- 
pears to have been first treated by an American entomologist in 
1819, when it was described as RTiynchxnus cerasi and figured (fig. 3) 
by W. D. Peck, who considered it the cause of black-knot of cherries 
and plums, from the fact that the insect was reared from these 



HISTORY. 



17 




-An early illustration of the plum curculio, frequency used 
between about 1S30 and 1S50. 



excrescences. In his Entomology of North America, published in 
1831, Thomas Say refers to the curculio as Cryptorhynchus argula, 
and gives the opin- 
ion of his kinsman, 
Bartram, as to its 
destructiveness. A 
fairly extended ac- 
count of the insect ' 
is given by Harris 
in his Insects Inj ur- 
ious to Vegetation, 
published in 1841, 
and it was con- 
sidered at length 
by Dr. Asa Fitch 
in his address on 
the curculio and 
black-knot of plum 
trees, delivered be- 
fore the New York 
State Agricultural Society in 1860 (p. 839). 

The most complete account of the insect up to this time, however, 
was that by Dr. Isaac P. Trimble in his Treatise on the Insect 
Enemies of Fruits and Fruit Trees, published in 1865. In this work 
99 quarto pages are devoted to the curculio, accompanied by 8 
colored plates. Many observations are presented as a result of 
personal investigation. Important contributions to a knowledge of 

the insect are given 
in the articles by 
Walsh in the Prac- 
tical Entomologist 
for 1867 (pp. 75-79), 
and in the First An- 
nual Report on the 
Noxious Insects of 
Illinois (pp. 85-96). 
In the First Missouri 
Report, published in 
1869, Dr. C.V.Riley 
gives an extended 
account of the cur- 
culio, summarizing 
the knowledge con- 
cerning it up to that time, and in the Third Missouri Report (1871, 
pp. 11-29) gives further information on its life history, with an ex- 
17262°— Bull. 103—12 2 




Fig. 3. — Peck's figure of the plum curculio, published with his descrip- 
tion (Rhynchsenus cerasi) in 1819. 



18 THE PLUM CURCULIO. 

tended discussion of apparatus for jarring. Also during the same year 
there was published in the American Entomologist (vol. 1, pp. 130- 
136) a popular account of the curculio, this being a lecture given by 
Dr. Riley before the Illinois State Horticultural Society. Numerous 
references, or more or less extended articles, concerning this insect 
are to be found in the writings of the earlier entomologists, as William 
Saunders, William Le Baron, Townend Glover, A. J. Cook, J. A. 
Lintner, and others, but the writings of Walsh and Riley were per- 
haps of most importance. 

References to the plum curculio notably increased with the estab- 
lishment of the agricultural experiment stations. Dr. S. A. Forbes, 
in Illinois, had already given some attention to this insect, publish- 
ing interesting observations on the use of poisons in its control as 
early as 1885. Experiments in spraying with arsenicals had been 
undertaken by W. B. Alwood, working under the direction of the 
entomologist of the United States Department of Agriculture, begin- 
ning with the season of 1887, and an extended summary account of 
the insect, by C. V. Riley and L. O. Howard, was published in the 
Report of the Commissioner of Agriculture for 1888. During this 
latter year Prof. C. M. Weed, of the Ohio Agricultural Experiment 
Station, began experiments in the use of arsenicals in its control, 
which were continued during the two or three subsequent seasons. 
Similar tests were reported by Prof. A. J. Cook in 1887 from Michigan, 
and in 1890 Prof. C. P. Gillette, in Bulletin 9 of the Iowa Agricul- 
tural Experiment Station, gave results of experiments and observa- 
tions on the curculio and plum gouger carried out during the season 
of 1889. 

A specific investigation of the curculio as an apple pest was begun 
by Prof. J. M. Stedman in Missouri in 1900 and continued during 
1901 and 1902. Results of his investigations were given in Bulletin 
64 of the Missouri Agricultural Experiment Station, published in 
July, 1904. Prof. C. S. Crandall, in Illinois, began in 1903 a thorough 
investigation of the insect as an apple pest, continuing the work 
during the following year. Results of his investigations and studies 
on the plum and apple curculios are published in Bulletin 98 of the 
Illinois Agricultural Experiment Station (1905) and comprise per- 
haps the most comprehensive account of the life histories of these 
two insects thus far given, as well as results of experiments with 
arsenical sprays on a commercial scale. The year following Prof. 
Forbes, in Bulletin 108 of the Illinois Agricultural Experiment Sta- 
tion (1906), reported results of experiments with arsenical sprays 
on a commercial scale, showing in connection with the work of Prof. 
Crandall that notably less injury to apples resulted following the 
thorough use of arsenate of lead. During the same year Prof. M. V. 
Slingerland reported results of cooperative spraying against the 



DISTRIBUTION. 19 

curculio carried out during 1904 between the Agricultural Experi- 
ment Station of Cornell University (Bulletin 235) and certain fruit 
growers in western New York. Mr. E. P. Taylor, in Bulletin 21 of 
the Missouri State Fruit Experiment Station, reports results in 
spraying for the control of the curculio on apple as obtained by him 
in the Ozark regions of Missouri. Observations on the curculio and 
results of experiments are given by W. W. Chase in Bulletin 32 of 
the Georgia State Board of Entomology, published in 1910. 

Beginning in 1905, investigations of the curculio were undertaken 
by the Bureau of Entomology of this department, and more or less 
attention has been given to this insect up to the present time. The 
investigation has included an inquiry into the life history and habits 
of the insect in various parts of the country and the carrying out of 
experiments in spraying on a commercial scale in its control on 
peaches, plums, and apples. As a result of the work in 1905, recom- 
mendations concerning the use of an arsenate-of-lead spray on 
peaches were given in the Yearbook of the Department of Agriculture 
for that year (p. 329) and in Circular 73 of the Bureau of Entomology. 
In the course of experiments to determine the comparative value of 
the one-spray method in the control of the codling moth much infor- 
mation was obtained on the value of spraying for the curculio, the 
results of which were published in Bulletin 80, Part VII, of the 
Bureau of Entomology. 

A decided advance in spraying stone fruits, especially peaches, 
was made with the establishment of the practicability of the control 
of brown-rot, scab, and curculio on peaches by the use of a combined 
spray of lime-sulphur and arsenate of lead. Recommendations for 
the preparation and use of this spray were given in Circular 120 of 
the Bureau of Entomology, and in Farmers' Bulletin 440 results of 
further experiments and demonstrations were given. 

In the foregoing historical sketch it has been attempted to indicate 
only the principal contributions or landmarks in the progress of 
knowledge concerning this insect and the remedies against it. By 
turning to the bibliography (p. 219) the reader will find reference to 
most of the contributors, although the list of titles could still be 
considerably lengthened. 

DISTRIBUTION. 

The curculio is indigenous to the eastern United States, and has 
probably always occupied about its present range of distribution. 
In some of the earlier accounts of the insect the inference is given 
that it had gradually spread westward from more eastern regions. 
As shown elsewhere (p. 156), its injuries were first noted in the 
neighborhood of Philadelphia about 1736. 



20 THE PLUM CURCULIO. 

Under the caption, "The curculio in Michigan," a Mr. Adrian, 
writing in The Cultivator in 1852, says: 

I propose in this communication to speak of the progress of the curculio in southern 
Michigan. I have been a resident of Lenowee County for the last 18 years. The 
first depredations of this insect commenced about six years ago, the first season attack- 
ing only a few of our choicest plums; the succeeding year they were more numerous, 
and since continue to increase from year to year, puncturing every variety of plum 
and also cherries to a considerable extent and in some instances often, apples. 

Dr. Asa Fitch in his Essay, published in 1860, says: 

As an evidence of its steady progress and increase [in New York State] during the 
past 40 years, I may state that in my boyhood the wild plum trees in my own vicinity 
were often well filled with fruit. But, though thrifty trees are still growing on several 
of the same places, I have never since that time seen a ripened plum upon any of them. 

A more recent statement relative to the invasion by the curculio 
of new territory (in Wisconsin) within its range of distribution is 
that by Prof. E. S. Goff in Insect Life (vol. 6, p. 37) : 

Until recently the peninsula lying between Green Bay and Lake Michigan has 
been free from invasion by the curculio (Conotrachelus nenuphar), and until the 
present summer (1893) it has never been found in any part of this peninsula lying 
north of Sturgeon Bay so far as can be learned from fruit growers in that region. In 
consequence of this, plum growing is becoming an industry of some importance in 
that district. 

Prof. Goff further states as a result of personal examination that 
he found the curculio south of the bay, but that north of the bay 
no infested plums could be found, though a few wormy cherries 
were noted for the first time in the experience of the fruit growers. 
The invasion apparently proceeded from the southwest. 

Dr. B. D. Walsh, writing from Illinois in 1867, observes: 

Although the curculio now infests the cultivated species of plums (Prunus domestica 
Linn.) to fully as great extent as our common wild species (Prunus americana), yet 
it is only at a comparatively recent date that it attacks our cultivated plums, and 
since that epoch it has been occurring every year worse and worse and making 
onslaughts on other fruits, such as peach and cherry, and even the apple. 

"The curculio," said the Hon. D. B. Baker in 1855, "were unknown 
and never made their incursions into this region [Illinois] until some 
years after the organization of our State government, A. D. 1818. 
There can be little doubt, however, that the curculios have existed 
from time immemorial in our State, breeding in wild plums." 

Numerous opinions of a similar nature might be cited to indicate 
the belief that the curculio was not indigenous to certain regions, 
and that it put in appearance only after cultivated food plants 
had been grown for some years. It seems more probable to the 
writers, however, as stated by Walsh, that the insect has always 
been generally distributed over its range, subsisting on wild food 
plants. The introduction of cultivated fruits undoubtedly resulted, 



WESTERN LIMIT OP OCCURRENCE. 21 

within a longer or shorter time, in these being attacked by the insect, 
and as it became abundant its injuries were sufficient to attract the 
attention of observant growers. 

From records in literature and those obtained by the Bureau of 
Entomology the curculio is found to occur very generally at the 
present time throughout the Mississippi Valley and the territory to 
the eastward. Records of the insect are at hand from hundreds 
of localities, covering practically all of this territory. Interest 
attaches, however, to the western and northern limits of the occur- 
rence of the curculio, and especially to the consideration of factors 
which may have operated to prevent its further spread. 

WESTERN LIMIT OF OCCURRENCE. 

During the summer of 1910 it was possible to collect some data 
on the western limit of occurrence of the curculio. In early June 
Mr. John B. Gill, of the Bureau of Entomology, was instructed to 
proceed to Sherman, Tex., and from thence in a northwesterly 
direction (along the Fort Worth & Denver City Railway) to a point 
Where the curculio could not be found. Next, to proceed in a north- 
easterly direction (along the Atchison, Topeka & Santa Fe Railway) 
into territory where the species was abundant. Mr. Gill proceeded 
in this zigzag manner to the west and east of the one hundredth 
meridian, as far north as North Dakota, making collections at many 
points of wild and cultivated fruit which might be infested. This 
fruit was sent to the insectary at Washington where rearings were 
made. Owing to injury by late frosts, the fruit crop in some sections 
was very light or absent, and on this account the collections were 
not so representative as was desirable. 

At Sherman, Tex., the insect was found on peaches and cultivated 
plums, though no injury was observed on apples. Four curculios 
were reared from sendings of fruit from this locality. The insect was 
also found present at Denison, Tex., an adjacent town on the Red 
River, five beetles being secured from fruit sent in. At Arlington, 
Tex., curculio larvse were found in peaches and plums, but the attack 
in no case was severe. Three curculios were secured from fruit from 
this locality. 

At Wichita Falls, Tex., the curculio was found on Japan and wild 
goose plums and peaches, and evidence of its injury to wild plums 
was noted. From several collections of fruit sent in no curculios 
were obtained. 

At Quanah, Tex., no curculio attack was found, although the wild 
plums were slightly infested with the plum gouger (AntJionomus 
scutdlaris) . Plums collected from wild trees along a creek were sent 
in to the insectary and several plum gougers obtained, but no adults 
of the plum curculio. 



22 THE PLUM CUBCULIO. 

At Amarillo, Tex., also, no indication of the presence of the curculio 
was noted in the wild plums growing along the Canadian River, and 
including several small peach, plum, and apple orchards in the region. 
No curculios were reared from the fruit sent from Amarillo. At 
Canadian, Tex., an abundance of wild plums was found along the 
Canadian River, but no curculio attack was observed. No beetles 
were obtained from the fruit sent in from this locality, although 8 
plum gougers were obtained. 

Both wild and cultivated plums at Alva, Okla., showed injury from 
the curculio. Two beetles were obtained from fruit collected in that 
region and sent in to the insectary. 

The curculio was very much in evidence in the environs of Wichita, 
Kans., the next point visited, occurring in cultivated plums, and 
injury to apple was also noted. A total of 51 beetles was reared from 
three sendings of fruit from this locality. At Hutchinson, Kans., 
the insect was also abundant, infesting both wild and cultivated plums, 
apricots, and apples. Thirty-two beetles were secured from fruit sent 
in. At Salina, Kans., the insect was also in evidence, injury being 
noted in several orchards of cultivated plums as well as in this fruit 
growing wild. A total of 68 beetles was reared from fruit from this 
section, indicating its considerable abundance. 

At Colby, Kans., no signs of curculio injury were found, nor were 
any beetles reared from the small amount of fruit sent in to the 
insectary from this locality. At Norton, Kans., the point next 
investigated, conditions were very similar to those obtaining at Colby, 
fruit being very scarce. No signs of curculio injury were noted nor 
were beetles reared from fruit received from this place. 

At Grand Island, Nebr., the curculio was very much in evidence 
on wild and cultivated plums, a total of 74 beetles being reared from 
the fruit there collected. The insect was also present in numbers in 
wild and cultivated plums at North Platte, Nebr., a total of 57 
adults being obtained from several collections of fruit. At Northport, 
Nebr., the complete absence of both native and cultivated fruit 
prevented any observations whatever. 

However, at Sterling, Colo., in about the same latitude, curculio 
egg punctures were observed in wild plums, although they were 
nowhere abundant. No punctures were noted on apples during a 
careful search of several orchards. The fruit, however, was not 
abundant. From collections of wild plums sent in to the insectary 
two adults were reared. This appears to be the first record for the 
curculio from that State. 

At Rapid City, S. Dak., cultivated and wild plums were found 
infested by the curculio to a slight extent. A total of 18 adults was 
reared from material from this place. At Pierre, S. Dak., the work 



WESTERN LIMIT OF OCCURRENCE. 



23 



of the curculio was not much in evidence, although both wild and 
cultivated plums showed some injury. Fourteen beetles were reared 
from fruit from Pierre. At Aberdeen, S. Dak., practically all fruit 
had been destroyed and no observations on the curculio could be 
made. 

Conditions were very similar at Jamestown, N. Dak., the point 
next visited. No fruit whatever was in evidence and no observa- 
tions were possible. Also at Bismarck, N. Dak., the fruit had been 
completely destroyed. At Fargo, N. Dak, and Moorehead, Minn., 
an adjacent town, there was but. little in the way of fruit, although 
wild plum trees were in abundance in the Red River Valley. Four 
curculios, however, were reared from plums sent in. 

In this connection should be mentioned the record of the curculio 
at Aweme, Manitoba, collected by Mr. N. Criddle, and published in 
the Annual Report of the Entomological Society of Ontario for 1904, 
page 76. 

While the observations made during 1910 by Mr. Gill are far from 
as complete as desirable, yet it appears clear that the insect has not 
established itself to any extent west of about the one hundredth 
meridian. Sterling, Colo, (longitude 103°), is the most western point 
from which the species has been recorded. Observations are most 
complete for Texas, and according to the data at hand the insect is 
present as far west as Victoria on the south and Wichita Falls on 
the north. Although fruit was present at Quanah, Canadian, and 
Amarillo, Tex., no beetles could be found. The general conclusion 
would appear warranted that the insect is not able to extend its 
range much out of the humid area as defined in Merriam's Life-Zone 
Map. 

In Table I the localities above mentioned, with a few additional 
ones, are shown, with approximate longitude and with indications 
of the source of the record. 



Table I. — Western distribution of the plum curculio. 



Localities. 


Longitude 
(approxi- 
mate). 


Occurrence. 


Remarks. 


TEXAS. 


97 00 

94 30 

95 30 

97 00 

96 35 
96 30 

98 25 

99 45 

100 20 

101 45 

98 00 

99 30 


Present . . . 

do 

do 

do 

do 

do 

do 

Absent 

...do 

...do 

Present . . . 
...do 






Do. 




Specimens received from correspondent. 




Reared from fruit in 1910. 




Do. 




Do. 


Wichita Falls 


Do. 










Amarillo 




OKLAHOMA. 

El Reno 


Specimens received from correspondent. 


Alva 


Reared from fruit in 1910. 



24 THE PLUM CURCULIO. 

Table I. — Western distribution of the plum curculio — Continued. 





Localities. 


Long ; tude 

(appro xi- 

mate). 


Occurrence. 


Remarks. 


Wichita 


KAXSAS. 


97 20 

97 35 

98 00 

99 50 
101 00 


Present . . . 

...do 

...do 

Absent (?) 
...do 






Do 




Do. 






Colbv 






COLORADO. 





Sterling. 



NEBRASKA. 



Lincoln 

Grand Island. 
Xortb. Platte.. 



SOUTH DAKOTA. 



Aberdeen. 



Pierre. 



103 15 -Present. 



96 45 Present... 

9S 25 ...do 

100 50 ...do 



Reared from fruit in 1910. 



Specimens received from correspondent, 
Reared from fruit in 1910. 
Do. 



Fargo 


XOKTH 


DAKOTA. 


Jamestown 






Bismarck.. 






Aweme 


MANITOBA. 



9S 30 



100 25 
103 15 



96 50 
9S 45 



99 00 



(?) Destruction of fruit crop by cold pre- 

vented observations. 
Present . . . Reared from fruit in 1910. 
..do Do. 



Present. . . Reared from fruit in 1910. 

(?) Destruction of fruit crop by cold pre- 

vented observations. 
(?) Do. 



Present... Collected bv X. Criddle (Ent. Soc. 
Ont., 1904", p. 76). 



NORTHERN LIMIT OF OCCURRENCE. 

The data bearing on the distribution of the curculio to the north 
depend almost entirely upon records in the Reports of the Entomo- 
logical Society of Ontario and in Dr. James Fletcher's reports as 
entomologist of the Canadian Experimental Farms. The most 
northerly point is Aweme, Manitoba, previously mentioned in con- 
sidering the western occurrence of the insect. This is in north lati- 
tude about 49°. The insect is also recorded from Gore Bay, Mani- 
toulin Island, Ontario, north latitude about 46°, and at Ottawa 
and Owen Sound, Ontario. According to Prof. William Lochhead, 
the insect was quite prevalent in Quebec Province during 1909. 
There are three records from Xova Scotia, namely, Berwick, Wolf- 
ville, and Port William, all in the immediate vicinity of one another 
in north latitude 45° 30'. So far as we have been able to determine, 
the localities mentioned above mark the northern occurrence of the 
curculio. The insect apparently is quite prevalent throughout 
Ontario and the lower St. Lawrence region of Quebec Province. 

Table II gives these localities with the approximate north latitude 
and the bibh^D graphical references. 



DISTRIBUTION ACCORDING TO LIFE ZONES. 
Table II. — Northern distribution of the plum curculio. 



25 



Localities. 



Latitude. 



Remarks. 



Aweme, Manitoba 

Gore Bay, Manitoulin Island, Ontario. 
Ottawa, Ontario 



Owen Sound, Ontario. 

Quebec, Quebec 

Berwick, Nova Scotia. 



00 Collected by N. Criddle (Rept. Ent. Soc. Ont., 1904, 

p. 76). 
00 ! Wm. Saunders (Rept. Ent. Soc. Ont., 1880, p. 8). 
30 W. Hague Harrington (Rept. Ent. Soc. Ont., 1880, 

; P- 53). 
35 I Fletcher (Rept. Ent. Exp. Farms Canada, 1885). 
35 I Wm. Loehhead (Rept. Ent. Soc. Ont., 1909, p. 68). 
30 Fletcher (Rept. Ent. Exp. Farms, Canada, 1896, 
p. 255). 



SOUTHERN LIMIT OF OCCURRENCE. 

The most southerly location in the United States from which we 
have records of tins species is Victoria, Tex., in the southwest, and 
around Hampton, Fla., in the southeast. At the latter place the insect 
has been found very abundantly and it constitutes a very serious 
pest to peach growers. At Deland, Fla., to which is adjacent a 
considerable peach-growing industry, no trace of the insect could be 
discovered, although it should undoubtedly thrive in that locality. 
These observations, however, were made in 1905 and the insect in the 
meantime may have become established there. 

DISTRIBUTION OF THE CURCULIO ACCORDING TO LIFE ZONES. 

From the foregoing discussion it will be noted that the plum 
curculio is present in the humid area in all of the life zones except 
the Tropical. It is most abundant and destructive, however, in the 




Fig. 4.— Map showing by the shaded area the distribution of the plum curculio. (Original.) 

Upper and Lower Austral Zones. While generally present through- 
out the Transition Zone it would appear to be much less of a pest 
than to the southward. Sufficient data are not at hand to indicate 
its relative importance in the Canadian Zone, though it is probably 
occasionally quite destructive, as indicated by the observations of 
Dr. Fletcher, Prof. Loehhead, and others. In figure 4 the shaded 
area indicates the present distribution of the curculio in so far as we 
have been able to determine it. 



26 THE PLUM CURCULIO. 

REPORTED INTRODUCTIONS OF THE CURCULIO. 

There have been reports at different times of the introduction 
of the plum curculio into new localities in the United States and 
into foreign countries. Thus in 1889 it was reported by local news- 
papers as present in Los Angeles County, Cal., but the insect in 
question proved to be Fuller's rose-beetle (Pantomorus fulleri) (see 
fig. 8), a common insect in the West, feeding upon leaves of ever- 
greens, oaks, camellias, palms, carinas, etc. 

In Bulletin 51 of the Montana Agricultural Experiment Station 
the insect is stated to be present in the Bitter Root Valley, but this 
reported introduction was later found to be without foundation. 

The curculio was reported in British Columbia on plums, but upon 
investigation in the territory reported to be infested, none of the 
insects could be found. 

The curculio is the subject of a chapter in the Handbook of the 
Destructive Insects of Victoria, Part II, by Mr. Chas. French, in which 
he alludes to the discovery by a Mr. Parson, of Kent, of an insect 
injuring plums very similar to if not identical with the plum curculio. 
The correctness of this record, however, is plainly doubted by Mr. 
French, and his reason for a detailed consideration of the insect in 
the work mentioned results from his expressed fear that the species 
may before long find its way into Australia. Thus far, however, the 
insect appears not to have been introduced there. 

In Tasmania, during 1889, considerable excitement was aroused 
by the discovery in cherries around Hobart of grubs which were 
thought to belong to our North American plum curculio. Subse- 
quent records as to the correctness of this belief are wanting, but it is 
probable that the insect in question was some one of the native 
species. 

More recently, in 1900, the insect was reported in New Zealand, 
near Auckland, but careful search for it in the supposedly infested 
territory did not reveal any trace of its presence. So far as recorded, 
therefore, the plum curculio is limited to the territory previously 
indicated in North America. It appears remarkable that in the case 
of an insect infesting fruits in the larval stage it should not have 
become much more widely distributed in the United States and 
to foreign countries. In fact it is entirely reasonable to suppose 
that at one time or another the insect has been shipped along with 
fruit to various parts of the world, but that owing to certain con- 
ditions essential for its proper development it has not been able to 
establish itself. In any country with climatic conditions similar to 
those obtaining in the humid area of the United States it would 
doubtless thrive, however, and become as destructive as it is at the 
present time in North America. 



LOSSES DUE THERETO. 27 

LOSSES DUE TO THE PLUM CURCULIO. 

It is difficult to make even an approximate estimate of the shrink- 
age in value resulting from the attack of the plum curculio on its 
several food plants. While adequate statistics are not available 
on which to make accurate calculations of the value of these several 
crops in the territory occupied by the insect, an attempt has been 
made to indicate as closely as possible the approximate annual money 
loss from the curculio. These data were published, as a part of an 
article on the losses from deciduous-fruit insects, in the Report of the 
National Conservation Commission, Volume III, page 309. In this 
article the figures for the apple crop were obtained from the American 
Agriculturist and other figures from the Twelfth Census. That 
portion relating to the curculio is quoted below. 

Average apple crop in the infested territory, 1897 to 1907. 

Barrels " 34, 292, 700 

Estimated shrinkage of first-class fruit, 10 per cent 3, 429, 270 

Valud, at $1.25 per barrel $4, 286, 587 

Value of fruit as culls, at 30 cents per barrel 1, 028, 781 

Total losses to apples 3, 257, 806 

On apples this insect receives but little if any treatment aside from that given in 

codling-moth treatment. 
There are no available figures on the yield of peaches. It was thus necessary to 

determine this as accurately as possible on the basis of the number of trees, and a 

conservative yield which each should give. 

Trees in infested territory 90, 931, 542 

Assuming that one-fourth bear every year, producing an average of 1 crate 

per tree, valued at 50 cents, net value $11, 366, 443 

Estimated annual loss of 33 per cent 3, 788, 814 

Cost of spraying, jarring, etc 300, 000 

Total 4, 088, 814 

There are likewise no figures on the yield of the plum, prune, etc., and the yields of 
these fruits were determined in a similar manner. 

Trees in infested territory 15, 906, 398 

Assuming that one-fourth bear fruit every year at the rate of 1 crate per 

tree, at 50 cents value $1, 988, 299 

Estimated annual loss of 50 per cent 994, 149 

Cost of treatment, spraying, jarring, etc 250, 000 

Total 1, 244, 149 

TOTALS. 

Apple $3, 257, 806 

Peach 3, 788, 814 

Plum, prune, etc 994, 149 

Total 8, 040, 769 

Cost of treatments 550, 000 

Grand total 8, 590, 769 



28 



THE PLUM CUECULIO. 




Fig. 5. — The apple cureulio (Anthonomus 
quadrigibbus). (From Riley.) 



The foregoing shows a grand total of loss each year, including cost 
of remedial operations resulting from the attack of the cureulio, of 
about $8,500,000. This amount, while by no means large as meas- 
ured by the destruction caused by certain other insect pests, as the 
cotton-boll weevil, Hessian fly, etc., is nevertheless a heavy drain 

upon the fruit-growing industry of the 
country. Unquestionably this injury 
will be reduced more and more in the 
future following a more general adop- 
tion of spraying, especially of peaches 
and plums — now entirely feasible, as 
elsewhere shown (p. 214). 

The sum total of losses due to the 
ravages of the cureulio during the past 
175 years would amount to an exceed- 
ingly large sum, though its injuries have 
become especially noticeable within 
comparatively recent years along with the enormous development 
of the fruit-growing industry. During the past 25 or 30 years the 
total losses caused by this insect, to the 
various fruits which it attacks, would 
on a conservative estimate probably 
be not less than $100,000,000. 

INSECTS LIKELY TO BE MISTAKEN 
FOR THE PLUM CUECULIO. 

The work of the plum cureulio is 
well known to most fruit growers 
within its area of distribution, and 
many have seen the adult or beetle. 
Others, however, know the insect only 
from its work, or as the grub or worm 
in the peach, plum, or cherry. Not 
infrequently specimens of beetles are 
received by the Bureau of Entomology 
from correspondents who believe them 
to be the plum cureulio, and which, while mostly true snout beetles, 
are quite different from this insect. Among those thus likely to be 
mistaken for the cureulio are the following: 

The apple cureulio, Anthonomus quadrigibbus Say (fig. 5). 

The plum gouger, Anthonomus scutellaris Lee. (fig. 6). 




Fig. 6.— The plum gouger (Anthonomus 
scutellaris). (From Insert Life.) 



INSECTS LIKELY TO BE MISTAKEN EOB IT. 



29 



The acorn weevil, Balaninus victoriensis Chitt. (fig. 7). 
Fuller's rose-beetle, (Aramigus) Pantomorus fulleri Lee. and 
Horn (fig. 8). 




^fc, 




Fig. 7. — The acorn weevil (Bxlanin,u,3 viclorienih) . 
(From Chittenden.) 



Fig. 8. — Fuller's rose beetle {Pantomorus fulleri). 
(From Chittenden.) 



The imbricated snout-beetle, Epicserus imbricatus Say (fig. 9). 




Tig. 9. — Imbricated snout beetle (Epicxrus imbricatus). 
(From Chittenden.) 

Comparison of the illustrations of these several species with figures 
of the plum curculio will show important differences. 



30 



THE PLUM CURCULIO. 



DESCRIPTION. 



THE EGG. 

The egg of the plum curculio (see fig. 10) is rather broadly elliptical, dilute milky- 
white in color, the surface smooth and shiny; the micropyle is inconspicuous, and the 

ends indistinguishable . The length 
is variable ; measurements of many 
specimens show a variation of from 
0.43 to 0.72 mm., with a range in 
width of from 0.35 to 0.45 mm. The 
average size of 30 eggs was found 
to be 0.643 by 0.411 mm. 

THE LARVA. 

When full grown — length 6 to 9 
mm., breadth 1.75 to 2.5 mm.; a 
yellowish- white, footless grub- 
nearly cylindrical, slightly flattened 
on ventral side ; body curved toward 
ventral side, bow-shaped; sides of 
each segment from second thoracic 
to eighth abdominal expanded into 

a fleshy lobe above and below a depressed lateral line. (See figs. 11 and 12 and PI. I, 

fig. 3.) 

Head as broad as long, about 1 mm. each way; color nut-brown; epistoma, clypeus, 

labrum, and mandibles darker; epicranial suture and its continuation as a median line 




Fig. 10.— The plum curculio ( Conotrachelus nenuphar): 
Egg. (Original.) 






Fig. 11.— The plum curculio: Larva, showing structural details.— a, lateral aspect; 6, ventral aspect; 

c, dorsal aspect. (Original.) 



DESCRIPTION OF LARVA. 



31 



extending beyond the middle of the front also darker; frontal suture light yellow, sub- 
mentum yellowish white; antennae minute, one-jointed, situated at base of mandibles 
at ends of frontal suture; minute eye-spots usually present directly laterad and caudad 
of antennae; mandibles with two blunt teeth; palpi two-jointed; seven hairs on each 
side of the epicranium, two on the front, two on epistoma, two large and many small 
hairs on labrum, two on each mandible, two on sub men turn, two on mentum, one 








Genu l \ N **, 

1 \ >• 

Submenmia Stipct Htmirim 



Front 

. Eye 
^Antenna 
Clypeus 

Labrum. 

.Mandible 

^_— -Staxitlary palpuj 

~ Labial paipug 
'Palpifer 



Fig. 12.— The plum curculio: Head of larva, with Fig. 13.— The plum curculio: Head of larva, lateral 
parts named. Much enlarged. (Original.) aspect, with parts named. (Original.) 

on stipes, two on palpifer, and eight on lacinia; hairs arranged as shown in figures 
13 to 15. 

Thorax. — Prothcrax with a light brown chitinized shield on the dorsum and a 
slightly chitinized area on each side of the venter; a conspicuous oblong spiracle 
situated above the middle of the side, its long axis extending dorso-ventrally; three 
pairs of large hairs on the dorsum, two pairs of large and five pairs of minute hairs 
below the lateral line, arranged as shown in figures. 




Labrum 

^.-Mandible 
,*-——— Maxillary palpts 

Lacinia 

Labial palpi 

Mentum 

-/ — \- \ \- ^Submentum 



Fig. 14. — The plum curculio: Head of larva, ven- 
tral aspect, with parts named. Much enlarged. 
(Original.) 



^^^^^ Ttr-'rariormuxl* 

Fig. 15. — The plum curculio: 
Lateral, dorsal, and ven- 
tral aspects of right man- 
dible of larva, with mus- 
cles. Much enlarged. 
(Original.) 



Meso thorax and metathorax without spiracles; each with one pair of large and four 
pairs of minute hairs on the dorsum, a large hair on the upper and one on the lower 
lateral lobe, one pair of large and four pairs of minute hairs on the venter, arranged as 
shown in figure 11. 

Abdomen. — Segments 1 to 7 each with an oblong spiracle above the middle of the 
side, its long axis extending longitudinally; two pairs of large and three pairs of minute 
hairs on the dorsum, one large and one minute hair on each lateral lobe, and three 
pairs of minute hairs on the venter, arranged as in the figures. 

The eighth abdominal segment is smaller than the preceding and lacks the outer 
pair of large dorsal hairs. 



32 



THE PLUM CUECULIO. 




The ninth abdominal segment is considerably smaller than the preceding, truncate 
posteriorly, has no spiracles, and bears two pairs of large and one pair of minute hairs 
on the posterior dorsal margin and two pairs of minute hairs on the venter. 

The anus, surrounded by three anal lobes, is situated on the ventral posterior part 
of the ninth abdominal segment. 

„ „ , THE PUPA. 

/ Larima 

, , , , Length 4.5 to 7 mm.; breadth 2.3 to 3.75 mm.; 

V Labial palpus 

color white, in older specimens the eves becoming 

.Venlum . r . o 

reddish brown and then black and the mandibles 
- c -■•--> and the tarsal claws becoming chitinized and visible 

through the pupal skin. A round spiracle is visible 
on the side of the second to fifth abdominal seg- 
ments, that on the first segment being covered by 
Fig. 16.— The plum curculio: Dorsal the pad of the elytron, 
aspect of maxilla and labium of The hairs of the pupa, except those on the head, 
larva, with parts named. Much j and SQme Qn Ae prothorax ^^ f^ tuber . 
enlarged. (Original.) , , ., , * _ „ . , % „ 

cles and are easily broken oil. On the head there 

is a pair of large hairs near the vertex, a pair just above the eyes, a pair between the eyes. 
a pair on the front of the beak just above the insertion of the antenna?, a pair of smaller 
hairs lower down the beak, and a more widely separated pair of minute hairs still lower 
down the beak. There are eight pairs of hairs on the prothorax. two pairs on the 
mesoscutum. two on the metascutum. and two pairs on the distal end of each femur. 
The pads of the elytra are elevated into ridges, from which arise groups of hairs on 
tubercles, there being about seventeen hairs on each elytron. Abdominal segments 
1 to 6 each bear two pairs of dorsal and one pair of lateral hairs. The seventh segment 
has an additional pair of lateral hairs, while the eighth segment has only one pair of 




Fig. 17. — The plum eureulio: Pupa, showing structural details— a, ventral; b, lateral; and c, dorsal aspects. 

(Original.) 



dorsal and one pair of lateral hairs. The ninth segment has a stout spine and a hair 
rising from a tubercle on each apical angle, and a pair of hairs on the venter. (See 
fig. 17 and PI. I, fig. 4.) 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate II. 




Fig. 1.— Egg and Feeding Punctures on Young Wild-Goose Plum. Enlarged. 

(Original.) 




Fig. 2.— Nearly Ripe Wild Plums, Showing Egg Scars and Gum Exudation from 
Feeding Punctures. 'Original.' 

WORK OF PLUM CURCULIO ON PLUM. 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate III. 




Fig. 1.— Effect of Egg and Feeding Punctures, with Gum Exudations, on 
Ripe Japanese Plums. (Original.) 




Fig. 2.— Fall Feeding Punctures on Ripe Prunes. (Original.) 
WORK OF PLUM CURCULIO ON PLUM. 



FOOD PLANTS. 



33 



THE ADULT. 

Length 3.5 to 5.75 mm.; breadth 1.75 to 2.75 mm. This stage is too well known to 
require particular description. The original description by Herbst is given on pages 13 
and 14. (See PL I, figs. 1 and 2; PL IV, fig. 1; text fig. 18.) 




/ 



: \ 



Ifandible \ ^S 




J Lacinial teeth/ 



} \abialpatpi MaxilUry V aljw 



Labium 

Fig. 18. — The plum curcuiio: Mouth parts of the adult — o, and a', mandibles, lateral aspect; b, dorsal 
aspect; c, ventral aspect; d, maxillary palpus. Much enlarged. (Original.) 

FOOD PLANTS. 

The plum curcuiio feeds upon and oviposits in practically all 
pome and stone fruits, as the apple, pear, quince, plum, peach, 
cherry, nectarine, and apricot. Certain wild fruits are also more or 
less used, especially when those above mentioned are scarce, as 
Crataegus, crab apple, etc. There are records of oviposition in 
huckleberry, grape, strawberry, gooseberry, currant, and wild per- 
simmon (Diospyros virginiana). There are also numerous records 
in literature of the breeding of this insect in black knot (Plowrightia 
morbosa), which we were able to verify during 1910. Not all fruits 
used by the female for egg-laying purposes, however, furnish suit- 
able food for the growth and maturation of the larva, and from this 
standpoint the instinct of the parent beetle is often faulty. Never- 
theless, there is evident choice of fruits for oviposition and, as stated 
by Trimble many years ago, in about the following order: Nectar- 
ine, plum, apricot, apple, pear, and quince. This order of preference 
nearly agrees with that indicated by our own observations, but 
Trimble does not include the cherry and peach, which we would 
place after plum, with the position of nectarine doubtful, as we have 
made but few observations on this fruit. 

It must not be understood, however, that in the presence of all of 
these fruits the curcuiio will choose certain kinds to the neglect of 
others. As a matter of fact, in orchards of mixed fruits, as plum, 
peach., apple, and pear, all of these sorts will be freely punctured; 
but plums more so, as a rule, than the others. The insect undoubt- 
edly prefers smooth-skinned fruits, and in the case of plum, nectar- 
ine, and apricot, which are usually first to attain sufficient size to 
receive the eggs, these are always much used. Nectarines and 

17262°— Bull. 103—12 3 



34 THE PLUM CURCULIO. 

apricots arc very uncertain croppers throughout the range of distri- 
bution of the insect on account of early blooming and consequent 
injury by frost. During fruiting years, however, in the absence of 
treatment, practically none of the fruit of these varieties escapes 
puncturing. During June, 1910, one of the writers examined several 
hundred apricots from trees in a neglected home orchard near Blue- 
mont, Va., without finding a single specimen free from infestation. 

As a group, plums constitute the favorite food of the curculio, 
and the various species of wild plums were without doubt the original 
native food of this species, and are freely used at the present day. 
The early literature of the curculio abounds with references to its 
especial injury to cultivated plums, and growers of this fruit have 
complained bitterly of its ravages. With the extension of culture 
of other fruits, as peaches, apples, cherries, etc., its injuries to these 
fruits have likewise become more and more important. However, 
until in comparatively recent years the curculio was regarded as 
preeminently an enemy of plums. (See Pis. II and III, showing 
curculio injury to plums.) 

Cultivated varieties of plums appear to show variation as to sus- 
ceptibility to attack. There are frequent references in literature to 
the subject, but adequate data for conclusions are wanting. In an 
extended article Mr. D. B. Wier (Bulletin 14, old series, Division of 
Entomology, p. 39, 1887) presents under the caption "The native 
plums: How to fruit them — they are practically curculio proof," 
results of observations which led him to believe that native plums 
are especially sought for by the curculio for oviposition purposes. 
Thus— 

The first and most important is that of evidence showing that this insect seeks 
native plums in preference to all other fruits in which to deposit her eggs. This is a 
queer. fact in biology which naturalists will be inclined to dispute, namely, that an 
insect should seek and use seemingly by preference a fruit in which to lay her eggs 
wherein but very few of them will hatch and in which but one of such larvae as do 
hatch can be nourished on its substance to maturity. 

Further on he states: 

I found that for every egg that hatched, and the larvae had fed noticeably, that there 
were from 1,500 to 1,900 ovipositing marks of the curculio and that only one living 
curculio maggot was found in 3,100 to 2,500 plums examined, and in which her eggs 
had been laid. These percentages are from the June observations of these two years 
and coincide with previous observations. 

Mr. Wier also observes: 

The reason why the plum curculio does seek the native plums to oviposit in seems 
to be because of their very early and fragrant bloom. 

His observations that native plums are much sought for as places 
for egg laying and that the larvae are not able to develop therein, led 



FOOD PLANTS. 35 

Mm to recommend the planting of native plums among other sorts 
more subject to attack for the protection of the latter. In this way 
he believed that the curculio could be largely exterminated. To 
the conclusions and premises expressed by Mr. Wier, Riley and 
Howard have indicated their dissent in a footnote to the article in 
question and also in their article on the curculio in the Report of the 
Entomologist for 1887. 

Riley states in the First Missouri Report, page 53 — 

That they prefer smooth-skinned to rough-skinned fruit. 

That up to the present time the Miner and other varieties of the Chickasaw plum 
have been almost entirely exemjDt from their attacks and that in the Columbia plum 
the young larvae are usually drowned out before maturing. 

Under the caption "Plums for the million," Riley, in the American 
Entomologist, volume 1, page 92, further calls attention to the 
Miner and Columbia plums on account of their freedom from curculio 
injury. 

Observations by Prof. Gillette in Iowa in 1889 include results of 
studies of varieties of plums as to their attractiveness to the curculio. 
The following plums were examined and the percentages of injury 
by the curculio were found to be as stated: 

Per cent. 

Miner 2. 50 

Wolf 17. 30 

Chickasaw 15. 70 

Forest Rose 13. 60 

Native Seedling No. 1 8. 30 

Native Seedling No. 2 25. 80 

Native Seedling No. 3 5. 20 

Yellow Mira Bell 66. 00 

Black Prune 14. 00 

Bier 31.50 

Early Red 19. 00 

The four varieties last mentioned are of the Domestica, or Euro- 
pean type, the others being native. Mr. Gillette, in discussing the 
data, says: 

That of the European varieties an average of 46.8 per cent of all plums were injured, 
the maximum being in the case of the Yellow Mira Bell, the minimum of injury 
being to the Black Prune, namely, 14 per cent. The average injury to native plums 
and varieties was only 6.6 per cent, with maximum in the case of a native seedling. 
The several small trees of Prunus simonii carried their fruit to maturity without any 
signs of curculio injury. 

Mr. Gillette concludes that this insect has a decided preference for 
the domestica varieties. 

From our own observations we would place Japanese varieties 
(Prunus trijiora) and their hybrids and crosses at the head of the 
plum list, as most susceptible to curculio injury, and the varieties of 



36 THE PLUM CUKCULIO. 

Prunus americana last, as least susceptible. Between these would 
come such native species and their varieties as Prunus angustifolia 
(Chickasaw) and P. umbellata, the P. hortulana group, and varieties 
of the European plums (P. domestica). Practically all sorts of plums 
throughout the range of the insect are freely attacked, but the earlier 
and more tender-skinned kinds will evidently be most sought out for 
egg-laying and feeding purposes. 

With peaches, there appears to be little if any difference as to the 
amount of injury to the different varieties. (See Pis. IV to VI for 
illustrations of injury to peaches.) While the fuzzy skin of this fruit 
renders it less attractive to the insect than plums, peaches are, as a 
rule, generally used where the insects are at all abundant. In the 
South, where early and midseason varieties are almost exclusively 
grown, wormy fruit is always in evidence at picking time. In the 
Middle States, but especially in the Northern States, wormy ripe 
peaches are less frequently seen, although the injury to the young 
fruit may have been severe. Late-maturing varieties, as Salway, 
Smock, Bilyeu, etc., as stated by numerous observers, are more free 
from attack than midsummer and early varieties, growing under 
identical conditions. As these varieties ripen after most of the beetles 
have ceased egg laying, wormy peaches at picking time are corre- 
spondingly scarce. It is probably true, however, that during the 
active oviposition period of the beetles there will be no discrimina- 
tion in choice of fruit of the early, midseason, and later maturing 
varieties. 

In the case of the apple, the curculio appears to oviposit indiffer- 
ently in all varieties early in the season, but later, on account of the 
changing texture of the skin and flesh, uses preferably the more tender 
varieties and those which mature during the summer or early fall. 
Such varieties as grow and mature quickly are very generally badly 
deformed from the egg and feeding punctures where the insect is 
abundant, whereas on later-maturing varieties the injury will be 
more nearly outgrown. (See Pis. VII to IX for illustrations of cur- 
culio injury to apple.) Late-fall and winter sorts are, however, often 
badly injured. Trimble says: "The early apples, as the Sweet 
Bough and Early Harvest, will suffer more than later kinds," evi- 
dently referring to the knotty condition of the fruit when ripe. 

In regard to pears, all varieties appear to be about equally subject 
to attack. Larvae, however, are probably never able to develop in 
the fruit on the trees, and comparatively few do so in drop fruit, espe- 
cially such varieties as the Kieffer and LeConte. The injury to pears 
consists largely in deformity of fruit from the egg and feeding punc- 
tures. (See PI. X.) 

Sweet cherries are perhaps preferred to sour cherries, although 
varieties of both classes are freely punctured. Larvae are able to 



Bui. 103, Bureau of Entomology, U. S. Dept of Agriculture. 



Plate IV. 




Fig. 1.— The Adult Curculio on Newly Set Peach. Enlarged. (Original.) 




Fig. 2— Curculio Larva, or Grub, and its Work in Ripe Peach 

(Original.) 

WORK OF PLUM CURCULIO ON PEACH. 



Bui. 103, Bureau of Entomology, U. S. Dept of Agriculture. 



Plate V. 




Fig. 1.— Wormy Windfall Peaches. (Original.) 




Fig. 2.— Peaches Deformed by Egg and Feeding Punctures. (Original.) 
WORK OF PLUM CURCULIO ON PEACH. 



Bui. 1 03, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate VI. 




Fig. 1.— Deformed Ripe Peaches. (Original.) 




Fig. 2.— Gum Exudation from Curculio Punctures. (Original.) 
WORK OF PLUM CURCULIO ON PEACH. 



FOOD PLANTS. 



37 



develop in the fruit on the trees, and wormy ripe cherries are very 
generally present on the trees, and on the market. (See PI. XI.) 

There remains to be mentioned more particularly the recorded use, 
for egg-laying purposes and as food for larvae, of the so-called black- 
knot of cherries and plums. (See fig. 19.) Prof. W. D. Peck, in the 
Massachusetts Agricultural Repository (vol. 5, p. 312, 1819), records 
rearing of the beetles from grubs found in the warty excrescences of a 
cherry tree, for which reason he gave it the name of Rhynchsenus 
cerasi, or the cherry weevil. Grubs apparently the same as those 
found in the plums are stated to have been frequently observed in 




Fig. 19.— Black-knot of plum, showing, on the left, infestation by plum-curculio larvae. (Original.) 

the warts, which it was then thought were caused by this insect. 
The larvae observed by Prof. Peck went into the ground July 6 and 
on the 30th of the month the beetles began to appear. A resume of 
Prof. Peck's observations on the curculio are given by Harris, who 
recommends that the excrescences of plum and cherry trees be cut 
out each year after the last of June. He adds that the moose plum 
(Prunus americana) seems to escape the attack of the insect, for no 
warts are found upon it even when growing in the immediate vicinity 
of diseased foreign trees. In his Essay Dr. Fitch, in commenting 



38 THE PLUM CURCULIO. 

on the nature of black-knot, states that the larvae of the curculio are 
almost always found in these growths, and the grubs consume nearly 
all the spongy matter of the warts. Later he adds: 

We think the fact well established that this insect breeds in these black-knot excres- 
cences with about the same avidity that it does in young fruit, notwithstanding these 
substances are unlike each other. 

Dr. Fitch expresses the belief that the curculio also resorts to the 
bark of different fruit trees in which to deposit its eggs when it can 
find no young fruits to meet its wants, and cites Melsheimer's (A 
Catalogue of the Insects of Pennsylvania, 1806, p. 28, No. 589) state- 
ment 50 years earlier that the curculio bred in the bark of peach trees 
as well as in the fruit. Dr. Fitch also records finding numerous 
curved incisions in the bark of pear resembling those made by the 
curculio, causing little blister-like elevations, containing from 4 to 
6 minute footless maggots which he thought belonged to the curculio, 
the insect wintering in the larval condition in the bark. In the First 
Missouri Report Riley states that the curculio deposits and the 
larvae mature in the black-knot of plum, and quotes Dr. Hull to the 
effect that it oviposits in vigorous shoots of peach, but that the larva 
does not mature in these shoots. 

Dr. Trimble says that black-knot, so often found on plum and 
cherry trees, is used freely by the curculio. These knots are often 
several days in advance of the young fruit, and the female curculio 
has been known to exhaust her supply of eggs in them before the 
young cherries or plums on the same trees were full formed. These 
positive statements as to the breeding of the insect in black-knot are 
scarcely to be questioned. 

During the season of 1910 we were able to verify these records. 
From a quantity of fresh black-knot material cut from a European 
variety of plum in full fruit at Bluemont, Va., one beetle was reared. 
Mr. A. G. Hammar, however, at Douglas, Mich., found the curculio 
breeding very abundantly in black-knot on plums and cherries and 
succeeded in rearing many hundreds of adults. (See fig. 19.) The 
comparative scarcity of suitable fruit in the neighborhood was doubt- 
less responsible for the great extent to which black-knot was used by 
the insect. 

Fruits in which the larvse, fail to mature. — As already indicated, 
oviposition may occur in numerous fruits which are hardly fitted for 
the future development of the larvse. As will be shown under another 
caption (p. 56), there is a considerable mortality of eggs and larvae in 
all classes of fruit which do not fall to the ground; but in the case of 
pears, and doubtless the grape, huckleberry, persimmon, and similar 
fruits recorded as used for egg laying, the larvae would in most cases 
be unable to mature. This has been shown to be true in the case of 



LIFE HISTORY AND HABITS : THE EGG. 



39 



the pear, the young fruit of which upon falling dries, becoming more 
or less flinty. Many hundreds of Kieffer, LeConte, Duchess and 
other varieties of pears have been collected, but in only a few cases 
were adults reared therefrom. 

LIFE HISTOKY AND HABITS. 
THE EGG. 



NUMBER OF EGGS DEPOSITED. 

The number of eggs deposited by the curculio was long a matter 
of conjecture. Riley's estimate (First Missouri Report, p. 54) of 
from 50 to 100 has been generally quoted in the absence of definite 
observations. He further states that eggs are deposited at the rate 
of from 5 to 10 a day, the activity of beetles var}dng with the tem- 
perature. Prof. A. J. Cook, by dissection, found that a single female 
may contain 30 eggs. Dissections during early May, 1887, by Mr. 
W. B. Alwood showed the presence of only 1 or 2 fully developed 
eggs, although many immature ova were found. Late in May, how- 
ever, 4 to 10 eggs were found in each female. Riley and Howard 1 
in 1888 expressed belief in Riley's earlier estimate, as based on the 
rate of development, dissections, and observations. 

The first attempt to obtain more exact information on this point 
was apparently in 1902, during the spring of which year Messrs. 
Quaintance and Smith 2 made observations in Maryland on 9 females 
confined separately during their lives and supplied daily with fresh 
plums. Careful examinations of the fruit were made and the number 
of eggs deposited by each female daily recorded. 

The record is shown in abstract in the table below, from date of 
capture, May 14, to time of death of each individual. 

Table III. — Egg-laying records from 10 pluvi curculios, College Parle, Md., 1902. 









Eggs laid each week by each individual 








No. of individual. 


Mav 
14-20. 


May 
21-27. 


May 
28- 

June 
3. 


June 
4-10. 


June 
11-17. 


June 
18-24. 


June 
25- 

Juiy 

1. 


July 
2-8. 


July 
9-15. 


Julv 
16-22. 


July 

23-29. 


July 

30- 
Aug. 

5. 


Total. 


1 


37 
65 


75 
91 


43 
40 


20 
26 


24 
11 


14 
2 


14 


6 


3 


10 


21 


9 


276 


2 


235 


















4 


62 
70 
64 
17 
45 
65 
71 


102 
104 
67 
45 
83 
114 
79 


59 
64 
56 


51 
45 
51 


28 
36 
27 


2 

25 

5 














304 


5 


14 


9 


6 


20 


30 


13 


436 


(5 


270 


7 














62 


8 


14 
61 

77 




















142 


9 


60 
36 


39 
27 


25 
25 


10 
8 


8 


3 


5 
13 


10 
10 




397 


10 


349 






Total 


496 


760 


414 


289 


192 


9S 


46 


23 


12 


48 


71 


22 


2,471 







1 Rept. Ent. U. S. Comm. Agr., 1888, p. 59. 

2 U. S. Dept. Agr., Div. Ent. Bui. 37, n. s., pp. 105-107, 1902. 



40 THE PLUM CUECULIO. 

Table III. — Egg-laying records from 10 plum curculios, College Park, Md., 1902 — Con. 



I To. of individual. 


Date last 
egg laid. 


Date of 
death of 
beetles. 


Days un- 
der obser- 
vation. 


Days on 
which eggs 
were laid. 


Maximum 

number of 

eggs in 

one day. 


Average 
number of 
eggs laid 
per day. 


1 


Aug. 1 
June 19 


Aug. 2 
June 20 
May 22 
June 19 
Aug. 2 
July 10 
May 28 
May 31 1 
July 31 
July 26 


8 
38 

9 
37 

8 
58 
15 
19 
79 
74 


70 
32 


15 
15 


3.94 


2 


7.34 


3 




4 


June 18 
Aug. 1 
June 19 
May 26 
May 30 
Julv 28 
July 25 


36 
74 
37 
10 
17 
63 
57 


17 
18 
15 
12 
14 
19 
15 


8.44 


5. 


5.89 


6. 


7.30 


7. 


6.20 


8. 


8.35 


9 


6.30 


10 


6.12 







Escaped. 



In Illinois, in 1904, Prof. C. S. Crandall 1 made many interesting 
observations on 17 female curculios relative to their feeding and egg- 
laying habits. Some of these are shown in Table IV. 

Table IV. — Egg-laying records from 17 plum curculios on apples, Griggsville, III., 1904. 



No. of individual. 


Eggs 
laid. 


Date of 
first egg. 


Date of 
last egg. 


Date of 
death of 
female. 


Days un- 
der ob- 
servation. 


Days on 

which 

eggs 

were laid. 


Maxi- 
mum 

number 
of eggs 

in 1 day. 


Average 
number 
of eggs 
laid per 
day. 


1 


84 
235 
119 
31 
12 
18 
44 


May 25 
May 26 

...do 

...do 

May 30 
May 25 
May 26 


July 10 
Sept. 3 
July 8 
July 17 
June 13 
Aug. 5 
June 22 


July 24 
Sept. 15 
July 20 
Sept. 10 
June 16 
Sept. 26 
June 23 


63 
115 

59 
111 

25 
127 
32 


32 
84 
37 
14 
9 
12 
22 


9 
8 
9 
5 
2 
3 
4 


2.64 


2 


2.80 


3 


3.21 


4 


2.21 


5 


1.33 


6 


1.50 


7 


2.00 


8 




9 


19 
263 

98 


May 25 
May 26 
June 3 


July 1 
Aug. 10 
June 25 


July 26 
Aug. 30 
June 26 


65 
100 
35 


15 
69 
22 


2 
9 

8 


1.26 


10 


3.81 


11 


4.45 


12 




13 


197 


May 26 


Aug. 30 


Sept. 6 


106 


78 


6 


2.52 


14 




15 


160 
34 
252 
249 
125 
14 


May 26 
May 27 
...do 
May 25 
June 2 
June 10 


Aug. 1 
Aug. 17 
Sept. 9 
Aug. 4 
Julv 17 
July 18 


Aug. 9 
Sept. 1 
Sept. 23 
Aug. 10 
July 23 
Aug. 20 


79 
102 
123 

80 
62 

87 


59 
25 
87 
62 
42 
11 


8 
3 
9 
9 

8 
2 


2.71 


16 


1.37 


17 


2.90 


18 


4.01 


19 


2.98 


20 


1.27 






Total 


1,954 









The beetles were captured May 23 (one pair May 26) in the act of 
mating and separately confined in jelly glasses, and were kept indoors 
on a laboratory table. Fresh apples were supplied at regular inter- 
vals. Observations were continued until death of female, as shown. 

During the last four or five years numerous egg-laying records have 
been obtained by the Bureau of Entomology in different parts of the 
country. These and other life-history studies for the most part have 
been made under out-of-doors conditions, approaching as closely as 
possible those which obtained in orchards at the time. (See PL XII.) 

i 111. Agr. Exp. Sta., Bui. 98, p. 508. 



Bui. 103, Bureau of Entomology, U. S Dept. of Agriculture. 



Plate VII. 




Fig. 1.— Egg and Feeding Punctures on Young Apples. (Original.) 




Fig. 2.— Egg Punctures on Apple, Some Days Old. (Original.) 
WORK OF PLUM CURCULIO ON APPLE. 



Bui. 103. Bureau of Entomology, U. S. Deot. of Agriculture 



Plate VI 




Fig. 1.— Young Apples. Showing Scars from Egg Punctures. 'Original.) 




Fig. 2.— Ripe Apples Deformed and Knotty from Egg and Feeding Punctures of 
the Curculio. (Original.' 

WORK OF PLUM CURCULIO ON APPLE. 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate IX. 




Work of Plum Curculio on Apple. 

Fig. 1.— Imperfectly developed apple from tree in which curculio grubs matured. Fig. 2 —Small 
drop apples m which curculio grubs matured. Fig. 3.— Nearly ripe summer apple from ground 
showing extent of feeding by two curculio larvse. (Original.) 



LIFE HISTORY AND HABITS : THE EGG. 



41 



Table V gives by weeks the number of eggs deposited by 8 female 
curculios, as observed by Mr. Fred Johnson, at Youngstown, N. Y., 
in 1905. The beetles were taken while mating, June 6, and each 
pair separately confined in a jelly glass. Observations were made 
morning and evening, at which times also fresh food was supplied. 
At date of capture, June 6, no egg punctures were in evidence on 
fruit in orchards, and the records are doubtless complete. 

Table V. — Egg-laying records from 8 -plum curculios, Youngstown, N. Y. , 1905. 





Eggs laid each week by each beetle. 




17o. of individual. 


June 
7-13. 


June 
14-20 


June 
21-27. 


June 
28- 

July 
4. 


July 
5-11. 


July 
12-18. 


July 
19-25. 


July 
26- 

Aug. 
1. 


Aug. 
2-8. 


Aug. 
9-15. 


Total. 


1 


13 

20 
33 
22 
9 
17 
32 
46 


12 
21 
30 
28 
28 
20 
31 
16 


18 
25 
30 
20 
31 
22 
37 
18 


18 
27 
37 
28 
31 
33 
47 
13 


8 
28 
48 
20 
34 
27 
34 

5 


3 

30 
13 
16 
26 
16 
32 
4 










72 


2 


12 


6 


12 


1 


182 


3 


4 


15 
13 

8 
19 

1 


7 
4 
6 
14 


3 

4 

1 

11 




159 
180 
150 
257 


5 


6 


7 


8 












Total 


192 


186 


201 


234 


204 


140 


68 


37 


31 


1 


1,294 




No. of individual. 


Date last 
egg laid. 


Date of 
death of 
beetles. 


Days under 
observa- 
tion. 


Days on 
which eggs 
were laid. 


Maximum 

number of 

eggs in 

one day. 


Average 
number of 
eggs laid 
per day. 


1 


July 12 
Aug. 10 
July 14 
Aug. 6 


/July 16 
\-.do, , 
/Sept. 1 
\Sept. 10 
/July 15 
\July 20 
/Aug. 22 
\Sept. 3 
/Oct. 3 
lOct. 12 
/Sept. 28 
(Oct. 4 
/Aug. 20 
(Aug. 26 
/Sept. 23 


39 
39 

85 

94 

38 

43 

76 

88 

118 

127 

113 

119 

74 

80 

108 


} 27 
} 54 
} 37 

} « 

} 49 
} 45 
} 58 


5 
8 
11 
11 
8 
9 
10 


2.67 
3.37 
5.16 
3.12 
3.67 
3.33 
4.43 


2 


3 


4 


5 


6 


dc 


R 


7 




8 


July io 








(.Sept. S 


9 




11 


4 


/ 















In Table VI are given records of observations by Mr. Johnson 
in 1906 at North East, Pa. Beetles were obtained by jarring, and 
the pairs in copula placed in individual jelly glasses on May 22. The 
food was Japan plums. 



42 THE PLUM CURCULIO. 

Table VI. — Egg-laying records from 10 plum curculws, North East, Pa., 1906. 





Eggs laid each week by each beetle. 




No. of individual. 


May 
23-29. 


May 

30- 

hme 

5. 


June 
6-12. 


June 
13-19. 


June 
20-20. 


June 

27- 

July 

3. 


July 
4-10. 


July 

11-17. 


July 

18-24. 


July 
25-31. 


Aug. 
1-7. 


Total. 


1 


9 
33 
33 

2 
2 
2 


12 

16 

13 

30 

35 

56 

6 

1 

3 

11 


14 

16 
20 
17 
30 
25 
16 
24 
28 
7 


8 
7 
8 
5 
11 
22 
8 

12 
12 
1 


7 


1 
1 

7 
4 
7 
8 
7 
4 
5 
4 


3 

4 
4 










54 


2 


6 


6 




1 


90 


3 


8 
2 
7 
9 
7 
6 
7 
1 


93 


4 


2 
3 








62 




2 


3 


2 




102 


6 




122 


7 


2 
3 


17 

16 

13 

9 


8 






71 


8 








06 


9 




7 
12 


3 
3 


1 


79 


10 






48 












Total 


81 


183 


197 


94 


54 


48 


18 


00 j 36 


8 


2 


787 




■ 






No. of individual. 


Date last 
egg laid. 


Date of 
death of 
beetles. 


Days under 
observa- 
tion. 


Days on 
which eggs 
were laid. 


Maximum 

number of 

eggs in 

one day. 


Average 

number of 

eggs laid 

per day. 


1 


July 10 
Aug. 4 
July 7 
July 14 
July 26 
July 2 
July 22 
July 15 
Aug. 1 
Julv 26 


/July 21 
\.-do.... 
/June 5 > 
\Aug. 28 2 
/July 28 
\..do..,. 
/July 13 
\July 14 
/Aug. 16 
\..do , , 
/Aug. 13 
\Aug. 10 
/June 14i 
\July 202 
/July 18i 
\July 262 
/Aug. 27 
t.do..., 
/July 28 


60 

60 

114 

2 98 

07 

67 

52 

53 

86 

86 

83 

86 

123 

2 05 

127 

2 05 

97 

97 

67 


} 30 
} 32 
| 32 
| 26 
} 37 
| 32 

} " 

} 28 
| 35 
1 22 


6 

16 

15 

6 

11 

16 

4 

7 

6 

5 


1.80 


2 


2.81 


3 


2.91 


4 


2.40 


5 


2.76 


6 


3.81 


7 


2.09 


8 


2.36 


9 


2.26 


10 


2.18 








\July 










/ 

















i Male. 



2 Female. 



In Table VII are records of eggs laid and of egg punctures by four 
pairs of beetles kept in the insectary at Washington in 1905. 

Table VII. — Egg-laying records from 4 pairs of the plum curculio, Washington, D. C, 

1905. 

EGGS LAID EACH WEEK BY EACH BEETLE. 



No. of pair. 


May 
11-17. 


May 
18-24 


May 
25-31. 


June 
1-7. 


June 
8-14. 


June 
15-21. 


June 
22-2S. 


June 
29- 

July 
5. 


July 
6-12. 


July 
13-19. 


July 
20-26. 


Total. 


1 


104 
40 
48 
40 


84 
56 
57 
16 


109 
60 

65 
8 


40 
44 
37 
32 


53 
29 
16 
30 


50 
35 
23 


50 
14 
17 


21 


17 


28 


1 


557 


2 


278 


3 










263 


4 










126 




Total 


















232 


213 


242 


153 


128 


108 


81 


21 


17 


28 


1 


1,224 









LIFE HISTORY AND HABITS I THE EGG. 



43 



Table VII. — Egg-laying records from 4 pairs of the plum curculio, Washington, D. C, 

1905 — Continued . 

EGG PUNCTURES MADE EACH WEEK BY EACH BEETLE. 



No. of pair. 


May 
11-17. 


May 
18-2*4. 


May 
25-31. 


June 
1-7. 


June 
8-14. 


June 
15-21. 


June 

22-28. 


June 
29- 

July 
5. 


July 
6-12. 


Julv 
13-19. 


July 

20-26. 


Total. 


1 

2 


112 
77 
61 

51 


SS 
54 
65 
11 


110 
70 
Gl 
13 


48' 
52 
39 
28 


51 
41 
16 

28 


59 
44 
25 


67 
12 
22 


26 


19 


34 


2 


616 
350 


3 










289 


4 










131 


















Total: 


301 


21S 


254 


167 


136 


128 


101 


26 


19 


34 


2 


1,386 


No. of pair. 


Date last 
egg laid. 


Date of death 
of beetles. 


Days under 
observa- 
tion. 


Average 
number of 
eggs laid 
per day. 


1 


July 21 
June 26 

June 26 


Aug. 28 2 


2 110 

157 
2 57 
154 
257 
139 


4.95 




/July 7 
\.-..do 
/July 3 
\July G 
/June 1 


l 


| 6.19 
| 4.60 
1 3.23 




2 

1 






2 






31 












\ 


ao 









* Hi 




1 





1 Male. 



2 Female. 



The beetles were captured at Arundel, Md., on the 9th of May by 
jarring plum trees. All caught were inclosed together under a bell 
jar until May 11, when the pairs were separated and placed in indi- 
vidual jars. From three to five fresh plums were added at intervals 
of one to four days, and those taken out were carefully examined. 
After about June 10 apples and plums were used as most convenient. 

The insects were kept under a temperature considerably higher 
than out of doors, namely, in the insectary building. The prolificacy 
of these individuals is not greater on the whole than in the case of 
those observed at College Park (Table III), but the death of pairs 
2, 3, and 4 was evidently hastened beyond what would occur under 
normal conditions. 

In every case more egg punctures were made than oviposited in, 
though the difference in the case of pairs 3 and 4 is less than with 
pairs 1 and 2. 

In the curculio egg record on peach, Myrtle, Ga., 1906 (Table VIII), 
the beetles were captured by jarring, April 5, and taken in copulation 
some hours later. Each pair was separately confined in a jar and 
supplied with peaches until July 25. As all peaches had been gath- 
ered from the trees by this date, foliage was supplied subsequently, 
which fact no doubt hastened their death, as most individuals died 
within a few davs. 



44 



THE PLUM CURCTTLiO. 



Table VIII. — Egg-laying records from 9 plum curculios, Myrtle, Ga., 1906. 





Eggs laid each week by each, beetle. 




No. of individual. 


CN 

p. 


OS 
tH 
1 
CO 

ft 


CO 
(M 

ft 
< 


CO 
C3 

1 

CN 

ft 

<! 


o 

>> 


1* 
>> 

03 


00 
03 


CO 

J, 

CN 

03 


i 

V 

a 
a 
>-> 


CO 

1 
t>. 

o> 
Cl 

3 

Hi 


o 
a> 

a 

3 


t~ 

CN 
1 

rH 

CN 

<L> 

a 

3 

1-5 


•* 
3 

a 

3 


2 

3 
is 


oo 
3 


O 

3 


"os 
o 


1 


4 
3 
11 
4 


4 

3 

13 

3 

1 

6 

8 

13 

11 

62 


3 

2 

10 

4 


25 

6 

38 

17 


6 

3 

20 


5 


1 


6 


17 


4 


1 


14 


10 








100 


2 








17 


3 


24 
13 


13 

9 


11 
4 


2 
6 


2 


2 


8 










154 


4 










60 


















1 


6 


18 
4 

12 
2 

58 


4 
7 
5 
6 

41 


22 
13 
25 
30 

176 


8 
4 
3 
6 

50 


11 


5 


5 
4 


5 
3 


3 


2 


8 










97 


7 










43 


8 


7 
23 

83 


















65 


9 


20 

48 


10 
40 


33 


9 
18 


5 
10 


10 
40 


3 
13 


1 
1 





15 
15 


151 


Total 


688 







No. of individual. 


Date last 
egg laid. 


Date of 
death, of 
beetles. 


Days under 
observa- 
tion. 


Average 
number of 
eggs laid 
per day. 


1 


July 4 
May 7 
June 22 
June 6 


/May 18 1 
\ July 30 2 
/July 29 i 
\June 5 2 
/Aug. 1 1 
\ June 26 2 
/July 24 1 
\July 26 2 
/July 20 1 

L ( 2 ) 
/July 18 ' 
(Aug. 92 
/June 2 1 
\June26 2 
/June 18 1 
\..do2.... 
/Aug.10 1 
\Aug.ll 2 


143 

2 116 

U15 

2 61 

1118 
2 82 
•110 

2 112 

1106 

( 2 ) 

1 104 

2 126 
158 
2 82 
174 
2 74 

1127 
2 128 


}■ 3.57 
| 1.55 
\ " 5.31 
| 3.53 
} 1.00 
| 4.04 
} 2.26 
J- 3.82 
} 5.81 


2 


3 ; 


4 


5 


6 


June 22 
June 1 
May 16 
July 25 


7 


8 


9 





1 Male. 



2 Female. 



Comprehensive records were obtained at Siloam Springs, Ark., 
during the season of 1908 (see Table IX) . Curculios were jarred from 
plum trees April 17 and the same day 30 pairs were selected and sepa- 
rately confined in jars. The beetles were given fresh plums daily as 
long as plums were available, after which apples were used. Obser- 
vations were made daily. 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate X. 




Bui. 103, Bureau of Entomology, U. S. Dept of Agricultur 



Plate XI. 




Plum Curculio Injury to Cherries. Cherries Cut Open, Showing the Grub 
and its Work. (Original.) 



LIFE HISTORY AND HABITS: THE EGG. 



45 



Table IX. — Egg-laying records from SO 


plum curculio& 


, Siloam Springs, Ark 


, 1908. 




Number of eggs laid each week by each beetle. 




No. of individual. 


CM 
CM 

M 
ft 

< 


C3 

a 
i 

05 
CM 

ti 

ft 
< 


IN 

C3 

a 


en 
*? 

CO 

>> 

a 


CO 

2 

CM 

« 

a 


CM 

CO 

a 

3 

CM 

>5 
03 

a 


i 

CO 

cu 

1-5 


CD 

J* 
O 

CO 

a 

3 
l-a 


CO 

i 

CO 

a 

3 

1-5 


o 
1 

IN 

CO 

a 

3 

Ha 


t^ 

i 

3 

1-5 


00 

3 

H5 


IN 

3 

1-5 


00 

IN 

ei 

CM 

jj. 

3 

1-5 


hi 

3 

1 

05 

IN 

jj. 

3 
1-5 


3 

hi 
3 
■< 


OS 

hi 

3 
< 


"3 

E-< 


1 


12 
15 
15 
15 
18 
12 
12 


16 

18 

19 
7 

13 
7 

15 
6 
9 

20 
8 

18 
4 
5 
9 
5 

18 
2 


16 

17 

13 

7 

16 

12 

16 

7 

12 

17 

11 

21 

11 

5 

5 

9 

14 
6 


31 
38 
.44 
11 
30 
40 
26 
6 
9 
34 
15 
31 
19 
18 
19 
21 
31 
25 
3 


22 
40 
41 
12 


18 

37 

35 

4 


16 
27 

44 


25 
16 
33 


29 
31 

29 
14 


12 

23 
21 
8 


6 
13 
21 
11 


8 
5 

14 
2 


2 

"29" 
3 










213 


2 


1 
11 








281 


3 


9 


7 


3 


388 


4 


13 fi 


113 


5 












77 


6 


45 
27 
10 
9 
24 
13 
24 
14 
12 
19 
18 
18 
45 


42 
20 
17 

7 
22 

6 
19 
19 
11 
19 
13 
28 
23 


37 
27 
14 
11 
26 
7 
13 
16 
12 
16 
13 
26 


23 
22 
6 


25 
23 


20 
14 


14 
16 


18 
11 


7 
4 


6 

8 


1 

4 






309 


7 






245 


8 






66 


9 


2 
15 
5 
12 
4 
7 
16 
2 
8 




















59 


10 


26 
2 
7 

11 

12 
6 
8 

11 


35 
1 
8 

13 

26 
9 
7 

30 


14 
6 
2 

8 


21 

4 


14 












268 


11 




2 


3 






83 


12 










155 


13 


9 


1 


3 










132 


14 




i 




108 


15 


2 
4 
10 










1 




120 


16 


3 
6 


2 
12 






4 
3 






109 


17 


2 


5 


?, 




224 


18 


10 




111 


19 


1 


















-------- 




4 


20 



































21 


10 
9 
11 

7 
6 
4 


13 


12 


23 


24 


20 


34 


18 


30 


13 


11 


13 


19 


11 


3 


5 


2 


261 


22 


9 


23 


19 
2 
17 
12 
20 


20 
6 
15 
19 

19 


29 
7 
23 
38 
41 
7 
24 
30 


38 
9 
14 
48 
37 
9 
19 
28 


43 
2 
13 
48 
25 
6 
16 
32 


46 


22 


12 


8 


10 


7 


1 


2 








268 


24 








33 


25 


12 

38 
36 


13 
31 
24 


7 
17 
29 








1 

10 










121 


26 


6 
14 


13 
9 
1 


8 
8 
1 


2 
1 


2 
10 




10 


306 


27 


273 


28 


10 
10 
6 






34 


29 


12 

6 


17 
20 


19 
33 


















117 


30 


28 


24 


10 


9 


9 


2 










237 














Total 


254 


300 


343 


673 


619 


545 


536 350 


399 


195 


177 


133 


83 


49 


39 


14 


15 


4,724 









No. of individual. 


Date last 
egg laid. 


Date of 
death of 
beetles. 


Days under 
observa- 
tion. 


Days on 
which eggs 
were laid. 


Maximum 

number of 

eggs in one 

day. 


Average 

number of 

eggs per 

day. 


1 


July 18 

July 23 
Aug. 16 
July 17 
May 18 
July 30 
Aug. 4 
June 12 
June 8 
July 13 
July 31 

June 24 

July 18 
June 23 
June 26 
Aug. 4 
Aug. 6 
June 2 
May 17 


/Oct. 8 
\Oct. 21 


170 
183 


| 68 

72 
99 
57 
21 
78 
83 
30 
31 
75 
45 

\ 53 

60 
48 
53 
50 
69 
28 
2 

92 

} * 

} » 

21 
46 

78 
77 
19 
42 
73 


11 

10 
12 
10 
10 
12 
8 
5 
5 
8 
5 

7 

8 
5 
5 
5 
7 

10 
3 

8 

4 

10 

3 

5 
12 
12 
6 
6 
9 


3.13 


2 


3.90 


3 






3.92 


4 






1.98 


5 






3.66 


6 






3.96 


7 






2.95 


8 


July 172 
Sept. 11 1 
July 142 


286 

1 142 

2 83 


2.20 


9 


1.90 


10 


3.57 


11 : 


1.84 


12 


/June 28i 
\June 292 


167 

2 68 


2.92 


13 


2.20 


14 


June 28 2 
June 292 


2 67 

2 68 


2.25 


15 


2.26 


16 


2.18 


17 






3.25 


18 






3.97 


19 






2.00 


20 








21 


Aug. 13 
Apr. 26' 

July 27 

May 28 
July 17 
Aug. 19 
Aug. 4 
July 14 
June 8 
July 21 






2.84 


22 


/Aug. 31 
\Sept. 1 
/Sept 7 
\Oct. 6 


131 
132 
138 
168 


3.00 


23 


3.52 


24 


1.57 


25 






2.63 


26 


Aug. 30 


130 


3.92 


27 


3.54 


28 






1.79 


29 






2.78 


30 






3.24 









1 Male. 



J Female. 



46 



THE PLUM CURCULIO. 



In Table X is presented the egg-laying record of 18 beetles, as 
obtained by Mr. Hammar, at Douglas, Mich., during 1910. The 
beetles were confined June 7, and the last egg was obtained on July 
24. The period of oviposition is noticeably shorter than in several 
other records presented. 

Table X. — Egg-laying record of 18 plum curculios, Douglas, Mich., "1910. 





Eggs laid each week by each beetle. 




No. of individual. 


June 

7-13. 


June 
14-20. 


June 
21-27. 


June 
28-July 4. 


July 
5-11. 


July 
12-18. 


July 

19-26. 


Total. 


1 


14 

17 

11 

4 

6 


23 

29 

27 

13 

9 

9 

21 

16 

23 

21 

18 

19 

22 

9 


29 
35 
13 
22 

3 

37 
13 

6 
32 
10 
26 
20 

3 
12 
12 
19 

8 
29 


15 
60 
6 
24 
11 
16 
23 
18 
36 
24 
34 
18 








81 


2 


47 


13 




201 






57 


4 


8 
15 


3 

37 




74 




9 


90 




62 


7 




16 
8 
17 
27 
5 


12 
7 




85 


8 


9 
4 

7 




64 


9 




112 


10 


17 


4 


110 


11 


83 


12 








57 


13 










25 


14 






4 






25 


15 




19 
58 
12 
49 






31 


10 






6 

6 

70 






83 


17 










26 


18 










148 














Total 


72 


259 


329 


423 


229 


89 


13 


1,414 






No. of individual. 


Date last 
egg laid. 


Date of 
death of 
beetles. 


Days un- 
der obser- 
vation. 


Days on 
which eggs 
were laid. 


Maximum 

number of 

eggs in one 

day. 


Average 

number of 

eggs per 

day. 




June 29 

July 13 
June 30 

July 13 

July 24 
July 1 
July 16 
July 14 
July 6 
July 20 
July 5 
July 1 
June 25 
July 6 
July 3 
July 5 
July 8 

July 11 


/July 11 
\Aug. 15 
July 18 
/Aug. 22 
\Sept. 5 
/July 13 
\July 30 
July 29 
July 5 1 


34 

69 
41 
76 
90 
36 
53 
52 
28 


55 
55 


29 
26 
54 
41 


29 
30 
35 


} » 

34 

} » 

| 22 

20 

15 

28 

21 

22 

29 

16 

13 

5 

9 

9 

12 

10 

1 w 


11 
11 
10 

7 

10 

10 

6 



11 

9 

10 

10 

9 

4 

4 

IS 

4 

14 


5.06 




5.91 




4.07 




3.36 




3.46 




4.13 


7 


3.03 


8 


Aug. 1 ■ 
...do.... 


3.05 


9 


5 09 


10 


3.79 


11 


July 6 
July 3 
July 31 
July 18i 


5.19 


12 


4.38 


13 


5.00 


14 


2.78 


]f 


3.44 


10 


July 6 
July 13 
/July 12 


6.92 


17 - 


2.60 


18 


7.79 








\July 








1 













Escaped. 



LIFE HISTORY AND HABITS : THE EGG. 47 

All of the above records, with the exception of those from Illinois, 
are brought together in Table XI. A total of 12,602 eggs is shown 
from the 7 localities. At College Park, Md., the maximum number 
of eggs deposited was 426 and the minimum 62, with an average of 
274.55 eggs per individual. At Youngstown, N". Y., the range is from 
257 for the maximum to 72 for the minimum, with an average of 
161.75. At North East, Pa., 122 was the greatest number of eggs 
deposited by an individual and 48 the lowest, with the average only 
78.70. At Washington, D. C, under laboratory conditions the 
maximum number of eggs laid by a single curculio was 557, the 
highest of all records for this insect, and the lowest 126, averaging 
for the 4 individuals under observation 306. At Myrtle, Ga., the 
maximum was 154 and the minimum 1, although this latter record 
should perhaps be disregarded; the average was 76.44 eggs per 
female. The records at Siloam Springs, Ark., include a large number 
of eggs, namely 4,724, from 29 pairs, one of the beetles confined fail- 
ing entirely to oviposit. The maximum number of eggs by 1 female 
was 388 and the minimum 4, giving an average for all pairs of 162.76 
eggs. At Douglas, Mich., the greatest number deposited by a single 
female was 201, and the lowest 25, with an average for the 18 indi- 
viduals of 78.56 eggs. 

In comparing the number of eggs deposited by the different indi- 
viduals for the respective localities and the averages of all beetles for 
a given locality, great variation is to be seen. Certain females, 
perhaps sickly or otherwise abnormal, deposited very few eggs, 
although feeding freely. Others oviposited assiduously throughout 
their existence. The final average number of eggs per female for all 
localities is 144.85, ranging from 1 to 557 eggs. Although the ovipo- 
sition period is greatly extended, yet the bulk of the eggs is deposited 
rather early in the season. As shown under the heading of percent- 
ages of eggs deposited by the second, fourth, sixth, and eighth weeks, 
the proportion deposited by a given time varies much in the different 
localities. There is, however, a general agreement that the great 
majority of the eggs have been placed by the end of eight weeks. 
The averages of all localities, shown at close of Table XI, in view 
of the considerable number of observations doubtless indicate about 
the rate of oviposition which may be expected in orchards. Approxi- 
mately one-fourth of 'the total eggs are laid during the first two 
weeks, one-half during the first month, three-fourths within six 
weeks, and 88 per cent of the total within eight weeks after fruit is of 
size to be usable for oviposition purposes. 



48 



THE PLUM CUKCTTLIO. 



Table XI. — Combined weekly egg-laying records of all beetles of the plum curculiofor each 
locality and percentage of eggs deposited within two, four, six, and eight weeks from 
confinement. 



Localities. 



Total number of eggs laid each week by all beetles of 
the respective localities. 




"I* 



Sis 



College Park, Md 

Youngstown, N. Y . . 

North East, Pa 

Washington, D. C . . . 

Myrtle, Ga 

Siloam Springs, Ark. 
Douglas, Mich 



Total . 



496 
192 
81 
232 

58 
254 

72 



1,385 



760 
186 
183 
213 
62 
300 
259 



414 
201 
197 
242 
41 
343 
329 



289 
234 
94 
153 
176 
673 
423 



192 
204 

54 
128 

50 
619 
229 



108 

83 

545 



46 
68 
18 
81 
48 
536 
13 



23 
37 
66 
21 
40 
350 



153 
32 
46 
46 

130 
1,104 



2,471 
1,294 

787 
1,224 

688 
4,724 
1,414 



1,963 



1,767 



2,042 



1,476 



1,111 



810 



537 



1,511 



12,602 



Localities. 



Maximum 
number of 
eggs per 
individ- 
ual. 



Minimum 
number of 
eggs per 
individ- 
ual. 



Average 
number 
of eggs 
per indi- 
vidual. 



Percentages of total eggs deposited by 
end of — 



Second 
week. 



Fourth 
week. 



Sixth 
week. 



Eighth 
week. 



College Park, Md 

Youngstown, N. Y.. 

North East, Pa 

Washington, D. C . . . 

Myrtle, Ga 

Siloam Springs, Ark . 
Douglas, Mich 



436 

257 
122 
557 
154 
388 
201 



126 

1 

4 

25 



274. 55 

161. 75 
78.70 

306.00 
76.44 

162. 76 
78.56 



50.82 
29.21 
33.54 
36.35 
17.44 
11.71 
23.40 



79.27 
62.82 
70.52 
68.62 
48.98 
33.21 
76.59 



91.01 
89.41 
83.48 
87.90 
68.31 
57.83 



93.40 
97.52 
94.15 
96.24 
81.10 
76.58 
100.00 



Averages for all locali- 
ties combined 



144.85 



26.56 



55.04 



77.32 



LENGTH OF EGG STAGE. 

Little exact information as to the period of incubation of eggs of 
the plum curculio is to be found in the earlier accounts of this insect. 
Trimble (Insect Enemies of Fruits, p. 29) states that if the weather 
be cloudy and cool, a week or 10 days is required for the eggs to 
hatch, but that in very hot weather the young grubs will escape in 
4 or 5 days. Riley and Howard state that from 3 to 10 days are 
required for the egg stage, depending upon the weather. Other 
writers have given about the same periods. In 1904, in Illinois, 
Crandall determined the length of time required for hatching of 6 
eggs as approximately 4^ days for 4 and 4 days 9 hours for the other 
two. His observations were made on eggs kept under laboratory 
conditions. 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate XII. 




Fig. 1.— Out-of-Door House Used in Life-History Work. (Original.) 




Fig. 2.— Soil Cages Used in Obtaining Data on Life of Insect in Ground. (Original.) 



METHODS OF STUDY IN PLUM CURCULIO INVESTIGATION, 
BARNESVILLE, GA. 



LIFE HISTORY AND HABITS : THE EGG. 49 

During the past 3 or 4 years we have been able to secure records 
on the incubation period for many eggs in different parts of the 
country. 

Observations on the length of the egg stage under out-of-doors con- 
ditions were made at Youngstown, N. Y., in 1905, but are not as 
extended as could be desired. Nevertheless, the following data by 
Mr. Johnson are of interest: 7 eggs deposited from June 8, a. m., to 
June 9, a. m., had by June 15 developed as follows: 

2 larvae hatched, but still in egg cavity. 
1 larva escaped from eggshell. 
1 larva feeding at pit of fruit. 

1 larva in short burrow near egg. 

2 eggs unhatched. 

These figures in a general way would indicate a period for the egg 
stage of 6 to 7 days. 

Forty-six eggs deposited June 15 from 1 to 7 p. m., on June 20 at 
2 p. m. were found to have developed as follows: 

20 unhatched. 

15 larvae hatched, but still in egg cavity. 

11 larvae in burrows, one-fourth to one-half inch from egg cavity. 

This indicates an egg stage of approximately 4| to 5 days. 
Forty-three eggs deposited June 24 were found on June 30, at 6 
p. m., to be in the following condition: 

6 eggs unhatched. 

16 larvae in burrows, about one-eighth inch from egg cavity. 
11 larvae in egg cavity. 

6 larvae just burrowing out of egg cavity. 
4 larvae feeding at pit. 

The egg stage with this lot is from 5 to 7 days. 

At Washington, D. C, in 1905, Mr. A. A. Girault made many 
observations on the length of the egg stage, as shown in Table XII. 
The eggs were kept in the insectary, and the temperature on the 
whole averaged considerably higher than at the same time out of 
doors. The longest period of incubation was 5 days, in the case of 
30 eggs deposited on May 18, and the shortest period was 2 days and 
15 hours, for a lot of 22 eggs deposited on June 14. The average 
incubation period, as based on the total number of egg days, is 3.77 
days. (See also Table XIII.) 

17262°— Bull. 103—12 4 



50 THE PLUM CUECULIO. 

Table XII. — Length of egg stage of the plum curculio, Washiiigton , D. C, 1905. 



Eggs under 
observa- 
tion. 


Date of 
deposition. 


Approxi- 
mate length 
of egg stage. 


Total egg 
days. 


Average 

length of 

egg stage, 

by months. 


1 
40 

1 
60 
40 
30 
10 


May 8 
May 9-10. . 
May 9 
May 10-11. 

May 15 

May 18. . . . 
May 19 


Days. 
3.75 
3.75 
4.25 
4.00 
3.75 
5.00 
4.75 


3.75 
150. 00 

4.25 

240. 00 

150. 00 

150. 00 

47.50 


Days. 

4.10 

2.88 
2.75 


182 


745. 50 


June 7 

June 14 

...do 

June 28.... 
...do 


4.00 
2.50 
2.75 
3.50 
3.00 


10 

22 

25 

1 

1 


40.00 
55.00 
68.75 
3.50 
3.00 


59 


170. 25 


Julyl 
July 11.... 

...do 

July 17.... 


2.75 
2.75 
2.75 
2.75 


2 
2 
1 
1 


5.50 
5.50 
2.75 
2.75 


6 


16.50 







Total number of eggs 247 

Total egg days ■ 932. 25 

Average length of egg stage, days 3. 77 

Records of 140 eggs, covering the period from April 9 to June 16, 
1906, at Myrtle, Ga., are given in Table XIII. Although material 
under observation was kept in the laboratory, yet temperature con- 
ditions in this instance were not essentially different from those 
obtaining out of doors. 

Table XIII. — Length of egg stage of the plum curculio, Myrtle, Ga., 1906. 



Eggs under 
observa- 
tion. 


Date of 
deposition. 


Approxi- 
mate length 
of egg stage. 


Total egg 
days. 


Average 

length of 

egg stage, 

by months. 


1 
1 
1 
4 

8 
2 
29 
10 
38 
11 


Apr. 9 
...do 

Apr. 11.... 

Apr. 12.... 

Apr. 15 

...do 

Apr. 20.... 
...do 

Apr. 27.... 

Apr. 30.... 


Days. 
2.75 
3.00 
4.75 
4.25 
5.50 
6.75 
5.25 
5.25 
4.00 
3.00 


2.75 

3.00 

4.75 

17.00 

44.00 

13.50 

152.25 

52.50 

152. 00 

33.00 


Days. 

4.52 

4.53 
3.35 


105 


474. 75 


May 5 

May 20 

May 31.... 


5.75 
4.50 
3.25 


9 

6 
10 


51.75 
29.00 
32.50 


25 


113.25 


June 7 
June 16 


3.00 
3.50 


3 

7 


9.00 
24.50 


10 


33.50 







Total number of eggs 140 

Total egg days 621. 50 

Average 1 ength of egg stage, days 4. 44 



LIFE HISTORY AND HABITS : THE EGG. 



51 



The shortest period, .2 days 18.5 hours, April 9 to 12, was closely 
approximated later in the season, June 7. The longest period, 6 
days 21.5 hours, occurred April 15 to 22. The average egg period 
for the entire series is 4.44 days. 

In Table XIV are given records of 113 eggs, observed in 1907 at 
New Richmond, Ohio, on different dates during May and June. 
The longest egg period was about 6J days, on May 18, and the 
shortest 3 days and 5 hours, on June 20. The average egg period 
for all lots is 4.92 days. • 

Table XIV. — Length of egg stage of the plum curculio, New Richmond, Ohio, 1907. 



Eggs under 
observa- 
tion. 


Date of 
deposition. 


Approxi- 
mate length 
of egg stage. 


Total egg 
days. 


Average 

length of 

egg stage, 

by months. 


39 
31 


May 18.... 
May 23 


Days. 
6.25 

5.00 


243. 75 
155. 00 


Days. 
5.69 

3.65 


70 


398. 75 


June 17 

June 22.... 


4.00 
3.25 


23 

20 


92.00 
65.00 


43 


157.00 







Total number of eggs 113 

Total egg days - 555. 75 

Average length of egg stage, days 4. 92 

Data were secured on the egg period at Siloam Springs, Ark., 
during late summer from August 15 to 25, the time varying from 
3^ to 6 days, the average of the 18 eggs for the period being 4.66 days. 

Some egg records made under out-of-doors conditions in the 
insectary yard, at Washington, 1908, are given in Table XV. The 
period included from May 7 to 22 was marked by abnormally low 
temperature, and its effect upon egg development is clearly shown. 

Table XV. — Length of egg stage of the plum curculio, Washington, D. C, 1908. 



Eggs under 
observa- 
tion. 


Date of 
deposition. 


Approxi- 
mate length 
of egg stage. 


Total egg 
days. 


3 
1 
4 
5 
3 
1 
2 
1 
5 
3 
7 
1 
1 
3 
3 
1 
1 


May 7 

...do 

May 8 
...do 

May 8-9. . . 

...do 

...do 

...do 

May 9-10. . 
...do 

May 10-11. 
...do 

May 11.... 

May 13.... 

May 13-14. 

May 14 

...do 


Days. 
11.00 
10.75 
9.75 
10.00 
9.50 
9.75 
10.50 
10.75 
8.75 
9.50 
8.50 
8.75 
8.25 
8.00 
8.00 
8.00 
7.75 


33.00 

10.75 

39.00 

50.00 

28.50 

9.75 

21.00 

10.75 

43. 75 

28.50 

59.50 

8.75 

8.25 

24.00 

24.00 

8.00 

7.75 


45 


415. 25 







Total number of eggs 

Total egg days 

Average length of egg stage. 



45 

415.25 

.days.. 9.23 



52 



THE PLUM CUECULIO. 



The longest egg period was 11 days 2 hours, the shortest 7 days 18 
hours, the average length of all lots being 9.23 days. These figures 
are in wide contrast to those obtained at Washington in 1905, and 
indeed at all other localities, except for April, at Barnesville, Ga., 
and the early part of June at Douglas, Mich., in 1910. 

Comprehensive data were obtained by Mr. Hammar during 1910, 
at Douglas, Mich., for June and July, these months averaging some- 
what cooler than normal. A total of 944 eggs was observed under 
out-of-doors conditions, as detailed in Table XVI. 

Table XVI. — Length of egg stage of the plum curculio, Douglas, Mich., 1910. 



Eggs 
under 
obser- 
vation. 


Date 

of 
deposi- 
tion. 


Eggs hatching in specified days from 
deposition. 


Total 
egg 
days. 


4 


5 


6 


7 


8 


9 


10 


11 


12 


11 
8 
40 
22 
52 
46 
54 
28 
27 
36 
11 
50 
31 
33 
18 
14 
22 
36 
38 
33 
37 


June 9 
June 10 
June 11 
June 12 
June 13 
June 14 
June 15 
June 16 
June 17 
June 18 
June 19 
June 21 
June 22 
June 23 
June 24 
June 25 
June 26 
June 27 
June 28 
June 29 
June. 30 

To 

July 1 
July 3 
July 4 
July 5 
July 6 
July 7 
July 8 
July 9 
July 10 
July 11 
July 12 
July 14 
July 15 
July 17 
July 18 
July 19 
July 21 
July 22 
July 23 
July 26 
July 28 

Tc 












1 
2 

33 
19 

2 


4 
6 


4 


2 


117 
78 
353 
195 
408 
332 
362 
152 
137 
180 
52 
246 
156 
180 
110 
80 
129 
189 
198 
175 
185 




















7 

3 

40 

10 

4 


























10 
36 
30 
























20 
12 
2 










"h 

12 
6 

10 
1 

'§" 

11 


16 

25 

36 

8 

32 

18 

2 

5 

4 

7 

28 

24 

1 

37 
















































4 

7 
17 

3 

10 
13 

7 
11 
21 


2 






















4 
9 
































"T 


2 


































































647 


,al 


4,014 














13 

22 

12 

21 

10 

18 

16 

30 

40 

10 

18 

16 

14 

3 

6 

8 

8 

8 

10 

5 

9 








7 
19 
12 
14 
10 
2 
4 
25 
20 

"16' 
15 


6 












84 
129 
72 
123 
60 
78 
84 
175 
220 
60 
92 
95 
83 
18 
42 
40 
25 
25 
61 
39 
63 




3 
























h 


5 

"2 

12 
5 
20 

5 

"i" 


2 






































































5 


































5 


3 












3 














6 














8 
5 
5 
5 










































fi 
















3 

9 


1 




1 
















... 






297 






1,668 









Average length of egg stage for June 

Average length of egg stage for July 

Average length of egg stage for June and July. 



.days.. 6.20 
.do.... 5.61 
.do.... 6.02 



LIFE HISTORY AND HABITS: THE EGG. 



53 



At Barnesville, Ga., during 1910 the length of the egg stage under 
out-of-doors conditions was determined for different lots of eggs, 
during April, May, June, and July, including a total of 445 eggs, all 
as shown in Table XVII. 

Table XVII. — Length of egg stage of the plum curculio, Barnesville, Ga., 1910. 



Eggs 
under 
obser- 
vation 


Date 

of 

deposition. 


Eggs hatching in specified days from deposition. 


Total 

egg 

days. 


3 


31 


4 


41 


5 


51 


6 


61 


7 


71 


S 


81 


9 


91 


10 


101 


11 


HI 


12 


121 


13 


131 


33 
43 
93 


Apr. 8 
Apr. 9 
Apr. 11 

Total 

May 9 
May 10 
May 12 
May 17 
May 18 
May 19 
May 21 
May 23 
May 25 
May 26 
May 27 

Tota 

June 16 
June 17 
June 18 
June 20 
June 22 
June 23 
June 24 
June. 25 
June 27 
June 28 
June 29 
Tnnp an 


















5 


7 

9 


12 
8 


7 

IS 


1 
1 


1 




1 














262.5 

381.0 

1,018.5 
























3 
3 




3 






















32 


44 


14 






































169 






1,662.0 

85.0 
110.5 
140.5 
10.0 
13.5 
62.0 
134.5 
10.5 
61.0 
198.0 
49.5 














1 
5 
10 


"r 

3 


7 
2 


2 




















10 
14 
19 
2 
3 

14 
32 
2 
13 
45 
11 






























































1 


5 






























2 










































































4 
24 


8 
3 


2 
5 
1 
5 










































































1 








































8 
24 
11 






































17 


4 
















































































































165 




875.0 


Y 


1 




= 






= 


= 


= 


= 


_, 1 


= 


== 


= 


= 


= 


= 


1 
1 
3 
2 
1 
1 
2 
3 
6 
2 
5 
1 




















3.5 
3.0 
11.5 

8.0 
3.5 
4.0 
6.0 
11.0 
21.5 
7.0 
22.0 
3.5 










































1 
1 
1 


2 








































1 










































































1 








































2 

"i* 

1 










































2 
3 

"i" 
1 


1 
2 
1 




















































































































3 


1 






































































I 










































28 


Total 

July 1 
July 3 
July 4 
July 6 
July 7 
July 12 
July 14 
July 15 
July 18 
July 20 

Tota 




104.5 




















1 
2 
2 
17 
18 
9 
6 
10 
10 
8 

83 






1 






1 
































4.0 
9.0 
8.0 
54.0 
64.5 
27.0 
19.0 
40.0 
47.0 
33.5 






2 




































11 
1 

9 
4 


6 
13 


2 












































































4 














































































2 
5 










































2 


1 

6 
2 


2 
4 
1 








































































1 


4 








































































306.0 







1 



Average length of egg stage for April days. . 9. 83 

Average length of egg stage for May do. .. . 5.30 

Average length of egg stage for June do — 3. 73 

Average length of egg stage for July do — 3. 68 

Average length of egg stage for season do — 6. 62 

The gradual decrease in the length of the egg stage following the 
rising temperature is well shown, dropping from the average, 9.83 
days, for April to 3.68 days for July. The average for the four 
months is 6.62 days. 

Table XVIII gives a summary of the preceding data. There is 
seen to be a range of from 2\ days to 13^ days for the different 
localities, the averages varying from 3.77 to 9.23 days. 



54 



THE PLUM CURCULIO. 



Table XVIII. — Length of egg stage of the plum curculio, various localities. 
[From preceding tables.] 



Localities and years. 



Washington, D. C, 1905. . .. 

Myrtle, Ga., 1906 

New Richmond, Ohio, 1907. 
Washington, D. C, 1908. ... 
Siloam Springs, Ark., 1908.. 

Douglas, Mich., 1910 

Barnesville, Ga., 1910 



Eggs ob- 


Minimum 


served. 


period. 




Days. 


247 


2.50 


140 


2.75 


113 


3.25 


45 


7.75 


18 


3.50 


944 


3.00 


445 


3.00 



Maximum 


Average 


period. 


period. 


Days. 


Days. 


5.00 


3.77 


6.75 


4.44 


6.25 


4.92 


11.00 


9.23 


6.00 


4.66 


12.00 


6.02 


13.50 


6.62 



Remarks. 



Eggs kept in insectary. 
Eggs kept indoors. 

Do. 
Eggs kept out of doors. 
Eggs kept indoors. 
Eggs kept out of doors. 

Do. 



THE LARVA. 
HABITS OF LARVAE JUST HATCHED AND COURSE TAKEN IN FRUIT. 

After making its escape from the egg, the little curculio larva 
usually remains for a short period in the egg cavity before boring 
into the fruit. In a comparatively short time after hatching, how- 
ever, it has usually buried itself out of sight. Thus a larva hatching 
at 9.50 a. m. on wild plum remained in the egg cavity until 10.45 a. m., 
but had disappeared in the flesh by 11 a. m. A larva hatching at 
10.46 a. m. was found partly entered at 11.07 a. m. Three larvse 
found in their egg cavities at 9.40 a. m. entered the tissues at 10.20, 
10.26, and 10.40 a. m., respectively. A larva hatching on apple at 
9.30 a. m. did not succeed in getting out of sight in the flesh until 
1 p. m., though upon hatching it at once began to burrow. Frequent 
dissections from fruit, of larvae of known age indicate that within 2 or 
3 hours after hatching the fruit has been penetrated. 

The course which the larvse may take in the fruit is somewhat 
variable, though in general the pit or core is soon reached. Some 
detailed observations were made on this point by Messrs. Girault and 
Rosenfeld (Table XIX). 

Table XIX. — Course in fruit taken by newly -hatched plum-cur culio larvse. 



Dates of 
observa- 
tion. 


Kind of fruit. 


Location of 
puncture. 


Fruits 
exam- 
ined. 


Course taken by larvse in fruit. 


Apr. 20 
May 1 






1 

5 

o 


Straight into pit. 


Red June plum 

do 




Basal J 


end of pit. 
Into side of pit, then around to apical end. 
Do. 




do 




.... do 




1 
2 

1 
1 
1 
1 
1 
1 
1 






do 


Basal J 

Apex 


Straight in about ■& inch, then around to 


2 


do 


apical £ of pit. 




do 


Basal i 

Center side 

.....do 


Do. 






Do. 




do 


Do. 


3 


do 


do 


Do. 




do 




Do. 


5 














then in toward pit; then out toward side 
of fruit, and in an irregular manner down 
to about center of side and finally to pit; 



LIFE HISTORY AND HABITS: THE LARVA. 55 

Table XIX. — Course in fruit taken by newly-hatched plum-curculio larvx — Oontd. 



Dates of 
observa- 
tion. 


Kind of fruit. 


Location of 
puncture. 


Fruits 
exam- 
ined. 


Course taken by larvae in fruit. 


May 16 
20 
26... 


Red June plum 

Early Belle peach 




1 
1 
1 

1 
1 

1 
1 

1 

1 
1 

1 


In to base of pit. 
In to pit. 


Center side 

Basal i 

Apical i 

Basal i 

Apical \ 

do 


27 




center of side, then into pit. 
Into pit. 

Straight in and into pit. 
Straight into pit. 
In straight to apex of pit, and then around 

to center of other side of fruit. 
Into apical § of pit, then along pit to center 

of side. 
Into pit; around to center side and into pit. 
Into about center of fruit, then to basal §, 

and down toward pit. 
Straight into pit, then along pit to apical \; 

then down side of pit. 


28.... 


do 


30 


do 


30.... 


do 




do 


Apical \ 


3 


do 


6..., 


do 


Center side 

do 


9 


do 









Prof. Crandall has recorded observations on the course taken by 
larva? hatching in apples, as follows : 

The course taken by the larvae on emerging from the egg has been traced in a number 
of apples, and is found to be variable. In one apple examined the bore proceeded 
straight from an egg cavity near the basin to a point just beneath the skin on the 
border of the cavity. Another bore was traced in a spiral 2J times around the fruit. 
Other bores were found to be tortuous, but in no apple examined did the early bore 
extend to the core. 

LARVAL INSTARS. 

The number of molts made by the curculio larva in the course of 
its growth has not heretofore been determined, probably on account 
of the difficulty of following the growth of the insect in the fruit. 
Mr. Hammar, during 1910, in Michigan, determined the number of 
molts and length of the respective instars for 10 individuals, as 
shown in the following table: 

Table XX. — Larval instars of the plum curculio. 





Dates of molting. 


Individual No. 


Hatched. 


First 
molt. 


Second 
molt. 


Third 
molt. 


Left 
fruit. 


Adult. 


1 


June 28 
June 30 
.. do 


June 30 

July 2 

do 


July 2 

July 4 

do 


July 5 
July 6 
July 7 
July 10 
July 9 
July 8 
July 9 
July 11 
July 12 
do 


July 9 

...do 

...do 
July 15 
July 14 
July 11 
July 12 
July 16 
July 18 
July 17 


Aug. 4 
Aug. 10 
Aug. 14 


2 


3 


4 


July 1 
.. do 


July 3 
do. 


July 7 
July 6 
...do 
July 7 
July 8 
July 9 
do 


5 


Aug. 16 
Aug. 12 
Aug. 15 
Aug. 29 
Aug. 15 
Aug. 16 





July 2 
. do 


July 4 
do 


7 


8 


July 4 
July 5 
...do.. 


July 6 

July 7 

do 


9 


10 













56 THE PLUM CUECULIO. 

Table XX. — Larval instars of the plum curculio — Continued. 





Duration of larva linstars. 


Individual No. 


First 
instar. 


Second 

instar. 


Third 
instar. 


Fourth 

instar in 

fruit. 


Total days 
to adult. 


1 


Days. 

2 
2 
2 
2 
2 
2 
2 
2 
2 
2 


Days. 

2 
2 
2 
4 
3 
2 
3 
2 
2 
2 


Days. 

3 
2 
3 
3 
3 
2 
2 
3 
3 
3 


Days. 

4 
3 
2 
5 
5 
3 
3 
5 
6 
5 


37 


2 


41 


3 


45 


4 




5 .■ 


46 


6 


41 


7 


44 


8 


56 


9 


41 


10 


42 






Totals 


20 
2.0 


24 
2.4 


27 
2.7 


41 
4.1 


393 




39.3 







Measurements were made of the width of head-casts of the respective larval molts in the case of one 
larva, as follows: 0.306 mm., 0.425 mm., 0.595 mm., 1.02 mm. 

Head measurements of 19 larvae at time of leaving the fruit showed a range in width of from 0.935 to 
1.071 mm., the average of all being 0.998 mm. 

DEATH OP LARV.E IN FRUIT. 

There is much evidence to show that many larvae die within the 
fruit, though the cause, or causes, of this mortality is not easy of 
positive determination. In general, if the fruit falls at the time or 
shortly after the egg is deposited, this insures favorable conditions 
for growth of the larvae. If, however, the fruit remains on the tree, 
the chances are much more against their successful development, 
and in the case of some fruits, as the apple and pear, almost entirely 
so. Prof. Crandall has made interesting observations on the mortal- 
ity among larvae in apples. In a lot of 716 fallen apples, 169 curculio 
larvae were found, 103 of which, or about 61 per cent, were dead, from 
causes not established. Most of the larvae found dead were less than 
half grown, and many were not more than 2 or 3 days from the egg. 
Although it is not so stated, it is probably true that these larvae were 
killed while the fruit was yet on the trees. 

The mortality of larvae in fruit for the most part results appa- 
rently from the crushing effect due to the rapid growth of surround- 
ing tissues; and in the case of stone fruits, as peach and plum, the 
abundant secretion of gum is perhaps an additional factor. The 
extent of mortality also varies with the different kinds of fruit. 

Thus in the case of apple many observations show that larvae are 
almost never able to survive if the fruit remains hanging on the trees 
for some time after the hatching of the eggs. The eggs for the most 
part hatch, and the young larvae begin to feed inward, but before 
they penetrate far they succumb. Such larvae show evidence of 
having been crushed, and often the burrow behind them is well grown 
over. Apples punctured while still small are most likely to fall; and 



LIFE. HISTORY AND HABITS: THE LARVA. 57 

after the apple has grown to three-fourths inch or 1 inch in diam- 
eter the punctures have much less effect, though the fruit may fall 
during the thinning process of the tree itself. The egg and feeding 
punctures, however, usually- result in disfigurement of the fruit, often 
very extensive, as will be discussed under another heading. 

During the 4 or 5 years that the curculio has been under investi- 
gation no observations have been made wherein the larvae have sur- 
vived to maturity in healthy apples on the trees, with the one excep- 
tion, as observed by Mr. Johnson at North East, Pa., on July 16, 
1906, of the occurrence, in a ripening apple on the tree of the Yellow 
Transparent variety, of three nearly full-grown larvae. (See PI. IX, 
fig. 10.) As in this instance, it is possible that when eggs are depos- 
ited in summer varieties as they are beginning to ripen, the resulting 
larvae would mostly be able to survive, since the stage of rapid growth 
of the fruit has passed. On another occasion in this locality Mr. 
Johnson observed, August 1, 1906, in an orchard of the Baldwin 
variety, numerous small and highly colored apples on the trees about 
the size of walnuts, some of which contained full-grown curculio 
larvae, and other fruits showed their exit holes. Unquestionably in 
this instance the normal development of the fruit had been checked 
from other causes, though it had failed to fall. The condition is not 
essentially different from that when the fruit drops to the ground. 

In interesting contrast to the practically complete death of all 
larvae hatching in apples which remain on the trees, and to a large 
extent of those which do not drop until some days after hatching, is 
the condition found to obtain when eggs are deposited in confine- 
ment in apples removed from the trees. In such cases, as has been 
observed frequently, a large percentage of the deposited eggs pro- 
duces mature vigorous larvae. Figures obtained by Crandall, involv- 
ing 1,474 eggs deposited in fallen fruit, show that 1,238, or 83.92 per 
cent, of these resulted in mature larvae. 

In the case of pears, although these are oviposited in freely by the 
beetles, larvae appear never able to survive in fruit on the trees, and 
but rarely on fruit on the ground. Unlike the apple, the young pear, 
when it falls, tends to dry up, and on account of the stony tissue 
present becomes very hard. In 50 young fruits of the LeConte and 
Kieffer pear taken from trees at Myrtle, Ga., May 2, and bearing 
numerous egg-punctures, no live larvae were found, none of the punc- 
tures was fresh, and all were more or less outgrown. An examina- 
tion of the egg cavity showed in most cases, however, borings of the 
young larvae, and their dead bodies. 

In lots of Kieffer pears containing eggs, collected at Myrtle, Ga., 
April 9 and 20, the eggs were observed to hatch, but larvae failed to 
develop. Pears of this same variety collected from the ground April 
13 and 20 and May 9 gave no results except from one lot, 4 adults 



58 THE PLUM CTTBCTJLIO. 

being reared. Further attempts at rearing from pears in this locality 
gave no results. 

May 21 and 23, 1905, at Washington, D. C, and again May 30, 
1905, young Kieffer pears from trees were confined with beetles, and 
eggs were deposited freely. No larvae, however, succeeded in devel- 
oping. 

During the course of the season of 1905 many fallen pears were 
examined by Mr. Johnson at North East, Pa., and he found only a 
single curculio larva, about one-third grown, feeding in the core of a 
pear on the ground. No larvae were found in fruit on the trees. 

Observations on plums, wild and cultivated, in many localities 
show that there is also a high mortality among larvae where the fruit 
remains on the tree or if its dropping be materially retarded. Plums 
punctured while small are more apt to drop than if the fruit is one- 
third grown or over. This dropping of the smaller fruit and the 
shedding of the fruit by the tree itself enables the species to more 
than maintain itself. Larvae hatching in fruit which does not fall are 
ordinarily able to penetrate the flesh but a short distance before 
succumbing, perhaps due to the combined effect of the copious gum 
exuded and the pressure of the growing tissues. The evidence also 
is that the egg may be destroyed by the gum exuding at the punc- 
tured point, and our notes show the examination of many punctures 
in which the egg could not be found, or was crushed, the cavity being 
completely filled with gum. The number of eggs or larvae missing 
has been quite too large to be accounted for otherwise. Many plums 
of the Japanese and Domestica types and of wild native sorts have 
been examined when taken from the trees and bearing egg punc- 
tures, and the conclusion is evident that larvae are not able to survive 
during the rapid growing period, and, as in the case of the apple, 
their successful development depends on the falling of the fruit. 
After the fruit has become grown, and the ripening process begins, 
larvae are more likely to survive, and ripe wormy plums, especially 
of the cultivated Japanese sorts, are not infrequently to be met with. 

The development of the peach, with reference to its availability 
as a host for the curculio, may be divided into three stages. The 
first stage includes the time from the beginning of oviposition to 
near the time when the pits begin to harden, a period of 3 or 4 weeks, 
during which approximately 75 per cent of the total infestation of 
the season occurs. The fruit in this stage, though growing rapidly, 
does not exude gum upon being punctured and readily drops from 
the tree when infested by curculio larvae. (See PI. V, fig. 1.) Prob- 
ably no fruit infested at this time remains long on the tree. The 
second stage in the growth of the peach begins when the pits show 
the first signs of hardening and extends up to the ripening period. 



LIFE HISTORY AND HABITS: THE LARVA. 59 

At the beginning of this second stage there is a sudden cessation of 
both egg laying and feeding, and during the whole time the beetles 
refrain from puncturing the fruit except in occasional instances. 
The fruit in this stage exudes gum very copiously when punctured. 
(See PI. VI, fig. 2.) Relatively little growth is made while the pit is 
hardening, but in the few cases in which eggs are laid and hatched 
at this time the larvse are killed at an early stage by the flooding of 
their burrows with gum, the fruit failing to fall from the tree. The 
third stage includes the ripening period, when the beetles resume 
oviposition and the larvse are able to mature normally. It is at this 
time that all the infestation of ripe fruit occurs, though the number 
of individuals developing is small in comparison with those in the 
young fruit which falls off. 

Another factor in the mortality of larvse in drop fruit, as noted by 
Crandall in apples, is the effect of sunshine. According to this 
gentleman, no living larvae could be found in fruit exposed to the 
sun for a few hours, whereas fruit taken from under the shade of the 
trees contained a fair proportion of living larvse. An interesting 
experiment is quoted, bearing on the matter: 

In one box were placed 200 apples and in another 250, the latter being placed in 
full exposure to the sun. Later examination of soil in the respective boxes gave for 
the former 42 pupae and for the latter 3 only. 

As suggested by Prof. Crandall, this points to the advisability of 
following a method of orchard management which will insure as free 
access of the sun as possible. 

DESERTION OF FRUIT BY UNDERSIZED LARVAE. 

On many occasions it has been noted that larvse may leave the 
fruit before reaching maturity and burrow below the soil as for 
pupation. This premature abandonment of fruit is perhaps often 
forced by reason of the unfavorable condition of the latter, but in 
many cases this explanation will not suffice. Fruit in an excellent 
condition for feeding purposes has been often thus deserted. An 
unhealthy condition of the larva itself, as from parasitism, might be 
suspected, but rearings of such individuals indicate that this is not 
the case. Larvse have at times been observed to leave fruit, as in a 
glass jar without soil, and, in the absence of suitable surroundings for 
pupation, reenter the fruit and there finally pupate. It is doubtful, 
however, if there is any tendency of larvse to leave one fruit in search 
of another, and a faulty instinct seems most likely to account for 
this behavior. Larvse emerging from peaches and plums collected 
throughout the season (p. 62) at Washington, D. C, in 1908, varied 
in about the following proportion: Large, 45.25 per cent; medium, 



60 



THE PLUM CURCU'LlO. 



39.04 per cent; and small, 15.69 per cent. Adults were never reared 
from the small larvae, though the attempt was repeatedly made. 

At Barnesville, Ga., during 1910, observations were also made on 
this point. Among the first larvae of the season to leave drop fruit 
was a large number of undersized individuals. Many were not more 
than one-half normal length, and from this they varied to full size. 
The proportion of small larvae was greatest during the first week or 
ten days after larvae began leaving the fruit, the proportion becoming 
less and less until by two weeks after the first larvae began emerging 
practically all individuals were of normal size. In Table XXI is 
shown the proportion of undersized larvae during the period from 
May 2 to 21, when they were in evidence. 

Table XXI. — Record of undersized and normal larvse of the plum curculio from drop 
fruit from 31 peach trees, Barnesville, Ga., 1910. 



Dates. 


Larvse 
leaving 
fruit. 


Distinctly 

undersized 

larvae. 


Dates. 


Larvse 

leaving 

fruit. 


Distinctly 

undersized 

larvae. 


May 2 


49 
68 
119 
164 
175 
99 
110 
357 
240 
209 


Number. 
38 
33 
48 
66 
26 
26 
12 
80 
29 
28 


Per cent. 
78 
48 
40 
40 
15 
26 
11 
22 
12 
23 


May 12 


272 
159 

S6 
58 
48 
38 
33 
71 
102 
54 


Number. 
22 
6 
5 
2 
1 
1 


1 
1 


Per cent. 

8 


3 


13 


4 


4 


14 


6 


5 


15 


3 


6 


16 


2 


7 


17 


3 


8 


18 




9 


19 




10 . 


20 


1 


11 


21 


2 







NORMAL EMERGENCE OF LARV.E FROM FRUIT DURING THE SEASON. 

In order to determine over what period and in what abundance 
larvae left the fruit and entered the soil for pupation, as bearing on 
the period for cultivation for the destruction of the pupae, it was 
planned in 1908 regularly to collect, at frequent intervals through- 
out the season, all of that fruit which fell to the ground and to rear 
and record the larvae as they emerged from the respective lots of 
fruit. This work was done during 1908 at Siloam Springs, Ark., 
using all drop fruit for the season from 120 peach trees; and during 
the same year at Washington, D. C, by Mr. P. R. Jones, with both 
peaches and Japan plums, using all of the drop fruit on 10 peach 
trees, and in addition to the drop fruit from 8 Japan plum trees 
that from the trees at ripening time was also used. 

During 1910 similar data were obtained at Barnesville, Ga., and 
by Mr. Hammar at Douglas, Mich. In Georgia all of the drop fruit 
throughout the season from 31 peach trees was regularly collected 
and larvae recorded as they came from the respective lots. At 
picking time the fruit from 12 of the 31 trees was gathered and 



LIFE. HISTORY AND HABITS: THE LARVA. 



61 



larvae recorded, but for uniformity the estimated number of larvae 
from the fruit from the 31 trees is used in the table. 

In Michigan the drop and picked fruit from 15 peach trees was 
used, collections beginning June 30 and continuing to August 27. 

These records, it is believed, should show the normal seasonal 
history of the insects in this stage under orchard conditions. Such 



1750 

tsoo 

1250 

/ooa 

750 
500 

s 

£250 
\ 

\ 


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Z 9 /6 23 30 6 13 20 27 4 1/ ■ IB 2S" / <9 'S 






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1 

1 

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\ 1 




\ 


























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\ 1 
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V 






\ 
\ 
























1 \ 
1 \ 
1 \ 
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/ \ 

1 

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^ 


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^2Sjg; 


rtyz//^ 


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<jz/9qg^ 




s' 


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500 
750 
/OOO 
1250 
1500 
1750 








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nfr" 


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Fig. 20. — Diagram showing normal emergence from fruit of larvae of plum curculio during season 
at Siloam Springs, Ark., Barnesville, Ga., Washington, D. C, and Douglas, Mich. (Original.) 

records are evidently much more reliable than those which do not 
take account of all of the fruit for the season. 

In Table XXII are shown the totals emerging for each of the 
four localities by days, as also the number and percentages of larvae 
emerging by months. 

These same data, summarized by weeks, are shown graphically in 
figure 20. 



62 THE PLUM CUECULIO. 

Table XXII. — Emergence of plum curculio larvse throughout the season, from total 
fruit, in various localities, 1908-1910. 





Barnesville, Ga., 
1910. 


Siloam Springs, 
Ark., 1908. 


Washington, D. C, 
1908. 


Douglas, Mich., 
1910. 


Dates. 


a 
'So 

M 

ID 

a™ 

£>, 

o3,h 

"os 
o 

Eh 


a 
°B 

o 

03 
CD 

■3 

O - 

Eh 


o 

03 

CD 

a| 

o 

CD 

Ph 


g 

'ho 
CD 

S«; 

o3 ,b 

"c3 

O 


a 

o 

a 

A 
o 

03 
CD 

•8 

"o3 

o 


o 

03 

S-l 

So 

5a 

o 
SH 

CD 

Ph 


M 
fl 

'So 

*n 

OJ 

a„; 

CD [>> 

"3 

O 

En 


o 

a 

,=1 
CD 

03 
CD 

tH 

•8 
"a 
o 

&H 


o 

03 
CD 

a| 

03 g 
"5 

CD 
O 

J-i 
CD 

Ph 


"?» 

a« 

ol£ 

la 
o 
Eh 


fl 

o 

a 
^i 

o 

03 
CD 

U 

•2 
~St 
o 
Eh 


A 

CD 

03 
CD 

Ut 

al 

§ 

o 

Fh 

CD 

Ph 


May 2 


49 

68 

119 

164 

175 

99 

110 

357 

240 

209 

272 

159 

86 

58 

48 

38 

33 

71 

102 

54 

12 

22 

27 

26 

13 

6 

21 

6 

11 

10 
























3 
























4 
























5 
























fi 
























7 






















8 














| 








9 














I 








10 






















H 














J 








12 






6 
22 
28 
18 
154 
195 
177 
201 
374 
300 
291 
243 
166 
141 
164 
233 
232 
444 
136 
139 








' 1 








13 












1 








14 




















15 




















16 






















17 






















18 






















19 






















20 






















21 






















22. 






















23. 






















24 






















25. 










50 
45 
187 
318 












26. 




















27. 




















28.. 




















29. 




















30 . 










218 

297 












31... 






















2,665 


81.64 


3, 664 


61.89 


1,115 


16.92 










7 
3 
2 
5 
2 
2 
4 
3 
6 
3 
3 


154 

159 

219 

169 

140 

140 

84 

82 

104 

33 

45 

46 

41 

39 

27 

15 

32 

34 

33 

23 

5 

10 

16 

16 

9 

3 

9 

6 

12 

10 


287 
220 
181 
110 
174 
290 
236 
229 
180 
154 
249 
377 
172 
190 
140 
296 
107 
64 
127 
110 
139 
182 
131 
184 
76 
155 
97 
68 
25 
52 




2 




















3 




















4 




















5 




















6.: 




















7 




















8 




















9 




















10.. 




















11.. 


















. 


12 






















1 




















14 




















15 






















16 






















17 






















18... 






















19 






















20 






















21 






















22.... 






















23 






















24.. 






















25 






















23 






















27 






















28... 






















29 


1 




















30 
























42 


1.28 


1,715 


2S.97 


5,002 


75.93 


2 

2 

4 

32 

37 






July 1 




2 
2 
6 
1 
5 


50 
43 
34 
24 
29 




2 




















3 




















4 




















5 
























LIFE. HISTORY AND HABITS : THE LARVA. 



63 



Table XXII. — Emergence of plum curculio larvse throughout the season, from total 
fruit, in various localities, 1908-1910— Continued. 





Barnesville, Ga., 
1910. 


Siloam Springs, 
Ark., 1908. 


Washington, D. C, 
1908. 


Douglas, Mich., 
1910. 


Dates. 


60 

.a 

cm 

03 

Sri 

Co, 

"3 
O 

H 


o 

e 

o 

IS 
03 

o 

"3 
o 
En 


,d 

o 

03 
03 

CD 

boo 

sa 



CD 

o 

M 

CD 
Pi 


ho 

B 

a™ 

CD O, 

Co, 

03,0 

O 
Eh 


a 
o 

a 

03 
CD 

O 

o 

Eh 


xl 
o 

03 
CD 

&* 
+^ 

bO°. 
03 H 

d 

03 
CD 
U 
03 

Ph 


bo 

.a 

60 
03 

0a 

03 O, 

Co, 

CS,Q 

"o3 
O 
Eh 


a 
o 

a 

o 
03 
CD 

u 

■2 
"3 
o 

Eh 


a 
03 
03 

i~t 
o . 

CD O 
Md 
03 H 

fl 

03 

O 
t- 
03 

Ph 


bo 

.a 

bo 
u 

03 

a « 

03 o, 

g-S 

£>> 
03^ 

"oS 
O 


a 
o 

a 

03 

03 
03 
t-i 

o 

"o3 
O 


A 

03 
03 

s-i 

al 

d 

03 
M 

03 

P4 


July 6 


1 






9 
5 






16 
36 
39 
29 
10 






27 

43 

36 

41 

35 

17 

14 

91 

56 

31 

19 

140 

•68 

55 

17 

8 

15 

4 

15 

22 

34 

4 

5 

7 

6 

2 






7 


















8 


4 
1 
1 
1 


















9 






8 














10 


















11 






3 






11 










12 




















13 


2 

12 

10 

14 

6 

13 

4 

1 

3 

13 

12 

30 

29 

56 

51 

77 

35 

56 

26 






3 

7 
8 
14 
4 
5 
8 
3 
45 
63 
38 
35 
46 
38 
24 
29 
21 
11 
24 






6 
8 
8 
11 










14 .... 


















15 


















16 


















17 


















IS 










10 










19 
















20 










15 
17 
12 
12 
19 








21 














1 


22 


















23 


















24 


















25 


















26 




















27 










15 
4 
4 
3 
4 










28 


















29 


















30 


















31 




















458 


14.02 


467 


7.89 


469 


7.12 


889 


99 33 




29 
5 
5 
21 
13 
11 
5 
5 
5 


16 
24 
6 
8 
2 
2 
4 
4 
1 
4 
1 


1 






2 




















3 










1 












4 




















5 
















3 

1 






6 




















7 




















8 
















2 






9 




















10 






















11 
























12 






















13 








2 














































99 


3.06 




74 


1.25 




2 


.03 




6 


.67 














Total 


3.264 


3,264 


100. 00 


5,920 5.920 


100. 00 


6,588 


6,588 


100. 00 


895 


895 


100. 00 











In the above table, the Georgia records show a total of 3,264 larva? 
leaving the fruit between May 2 and August 9. A large majority of 
these, 2,665, or 81.64 per cent, issued during May; during June only 
42, or 1.28 per cent, issued, while during July, 458, or 14.02 per cent, 
was secured. August shows a total of 99 larvse, or 3.06 per cent. 
At Siloam Springs, Ark., in 1908 a total of 5,920 larvse issued, the 
interval covering the period from May 12 to August 13. Larvse to 
the number of 3,664, or 61.89, left the fruit during the period from 
May 12 to 31 ; while for June, 1,715, or 28.97 per cent, left the fruit, a 
total for the approximately 7 weeks of 5,379, or 90.86 per cent. 



64 



THE PLUM CURCULIO. 



July shows an emergence of 467 larvae (7.89 per cent) and August 1 
to 4, after which no more emerged, 74, or 1.25 per cent. 

At Washington, D. C, during 1908, a total of 6,588 larvae was 
reared, 1,115 emerging during the last 7 days of May. During June 
5,002 larvae left the fruit, a total for May and June of 6,117, or 92.85 
per cent. Only 7.12 per cent of the total-larvae emerged during July, 
emergence practically ceasing with that month. The Michigan rec- 
ords include only 895 larvae, of which 889, or 99.33 per cent, left the 
fruit during July. 

The foregoing data, with the additional records by Crandall from 
Illinois, are shown in Table XXIII with the dates of blooming of 
peach trees for that year. 

The relation of these data to the time of making cultivations is 
shown on page 176. 

Table XXIII. — Emergence by months of plum-curculio larvae in different localities. 





Approx- 
imate 


May. 


June. 


July. 


August. 


September. 






bi 

pi 




bi 

a 




bi 

1=1 




bi 

a 




bi 








date of 










be 




CX 




M 






Localities. 


full blos- 


* 








<3 




<D 




SB 








som of 


S 


P 


a 


a> 


a 


03 


a 


O) 


a 


Ol 






peach 




03 




03 




03 




03 




03 






trees. 


88 


el 


S8 


& 


S3 


a 


8 


S 


« 


M 


_j 






I 


a 


t> 


o 


> 


?, 


t 


g 


b 


2 


03 






03 






<3 




s 
















f} 


Ph 


i-I 


Ph 


a 


Ph 


Hi 


Ph 


h3 


Ph 


EH 




Mar. 15 


2,665 


81.64 


42 


1.28 


458 


14.02 


99 


3.06 






3,264 


Siloam Springs, Ark 

Washington, D. C 


Mar 18 


3 664 


61.89 


1,715 
5,002 


28.97 


467 


7.89 


74 


1.25 






5,920 


Apr. 6 
Apr. 20 
May 10i 


1,115 


16.92 


75.93 


469 


7.12 


2 


.03 






6,588 








889 
662 


99.33 
53.47 


6 

272 


.67 
21.97 






895 








254 


20.52 


50 


4.04 


1,238 











Apple. 



MANNER OF LEAVING THE FRUIT AND ENTERING THE SOIL. 

Upon completing its growth, the larva leaves the fruit in which it 
has been feeding, and soon makes its way beneath the soil. Fruit 
lying upon the ground will usually show, when examined, the small 
exit hole of the grub, mostly along the lower side where the fruit was 
in contact with the earth. An examination of 200 infested drop 
peaches showed these exit holes to be located as follows: Apex, 8; 
apical third, 64; center of side, 66; basal third, 46; base, 16. This 
shows that 88 per cent of the exit holes are along sides as against the 
ends, which is perhaps proportionate to the respective areas. In 
deserting the fruit on the trees, as peaches and cherries, the larva 
must fall, and this is probably not injurious to it. Once upon the 
ground, the instinct is immediately to get below the soil. The time 
occupied in accomplishing this will vary according to character of 
soil, whether cultivated or not, and the presence of crevices, etc. At 
this time especially the larvae are exposed to predaceous insects, par- 



LIFE HISTORY AND HABITS: THE LAEVA. 



65 



ticularly ants, and numerous larvae perish from their attack. Many 
larvae have been timed by the watch, and the interval occupied until 
out of sight below the soil has varied from about one-half to 50 minutes. 
Table XXIV includes observations made inGeorgia and in Washing- 
ton,D. C.,both in the orchard and in small jars in the laboratory. It 
will be noted that more time is usually spent in searching for a suitable 
place to enter than in actually working below the surface. The 
average time on the ground and until beneath the soil, in the data 
given, is about 12 minutes. A larger series of observations would 
probably change these figures somewhat. 

Table XXIV. — Time occupied by larvae of the plum curculio in entering soil. 



Localities 



Myrtle, Ga.: 
Laboratory . 



In orchard . 



Washington, D. C 
Insectary 



In orchard . 



Larva 
No. 



Time 
on soil. 



10.00 

2.07 
10.21 
9.13 
4.08 
9.59 
9.43 
10.22 
10.22 
4.16 
5.22 
5.22 
5.22 
5.22 
5.22 
5.22 
5.22 

1.26| 

1.30 
1.48 
2.23 
2.10 
2.44 
2.23 
2.55 

2.55 
3.33 
3.03 
3.20 
3.141 



Began 
to en- 
ter. 



10. 06 

2.15 
10. 21| 
9.14 
4. 10J 

10.00 
9.44 
10. 23 
10. 25 
4.18 



1.29 

1.59 
2.40 
2.36 
2.37 
2.46 
2.41 
2.55 

2.56 
3.34 
3.15 
3.22 
3. 155 



Be- 
neath 
soil. 



1.41 

2.19 
3.23 
2.40 
2.42 
2.47 
2.44 
3.11 

3.00 
3.36 
3.18 
3.25 

3. 104- 



Time 
occu- 
pied. 



Minutes. 
lli 



2.21 


14 


10.22 


1 


9.15 


2 


4.12 


4 


10.03 


4 


9.49 


6 


10.24 


2 


10.30 


8 


4.26 


10 


5.23 


1 


5.26 


4 


5.27 


5 


5.31 


9 


5.34 


12 


5.39 


17 


5.49 


27 



Kind of soil. 



Fresh sandy loam soil in glass jar, 
gently packed. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 
Dry sandy soil under peach tree. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Sandy garden soil in box, moder- 
ately compacted. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 
Clay loam, well cultivated. Larvae 
placed under plum tree. 

Do. 

Do. 

Do. 

Do. 

Do. 



TIME SPENT IN THE FRUIT (EGG AND LARVAL STAGES COMBINED). 

In 1904 Prof. Crandall determined, for Illinois, the time spent in 
apples (combined egg and larval stages) for 1,238 individuals. A few 
larvae left the fruit within 12 and 13 days from deposition of egg, and 
some spent an unusually long time in the fruit. The great majority, 
however, developed and left the fruit in about the average time. 
Table XXV gives his emergence records by months, and also the 
average period per individual within fruit for that month, 
17262°— Bull. 103—12 5 



66 THE PLUM CURCULIO. 

Table XXV. — Length of time spent in fruit by plum curculio, Illinois, 1904. 



Months. 



Total num- 
ber of 
larvae 

emerging. 



Percentage 
of whole. 



Average 
time in 
fruit. 



June 

July 

August 

September. 

Total 



254 
602 
272 
50 



20.52 

53.47 

21.97 

4.04 



Days. 

"18.07 
19.15 
21.55 
26. 00 



1, 238 



100. 00 



The average time for egg and larva in the fruit for the whole season 
was about 20 days. 

In Table XXVI are given records of a few observations from 
Youngstown, N. Y. (1905), and North East, Pa. (1906). 

Table XXVI. — Length of time spent in fruit by the plum curculio (egg and larval stages 
combined), Youngstown, N. Y., 1905, and North East, Pa., 1906. 





Eggs 
depos- 
ited. 


Date of depo- 
sition. 


I-zarvse emerged 


Ap- 
proxi- 
mate 

time 

in 

fruit. 


Total 
num- 
ber of 
larva? 
devel- 
oped. 


Total 
num- 
ber of 
egg and 
larval 
days. 


Aver- 
age 


Localities. 


Num- 
ber. 


Date. 


num- 
ber of 
days 

in 
fruit. 




43 
(?) 


June 24,1905 

fJune 1^,1906 

Uune 14.1906 
(June 15,1906 


II 

{ I 

6 
4 


July 10,1905 
July 12,1905 
July 13,1905 
July 14,1905 
July 9, 1906 
July 3,1906 
July 5, 1906 
July 3.1906 


Davs. 
16.00 
18.25 
19.00 
20.00 
25.50 
21.00 
20. 75 
18.00 


1" 

} ' 

6 
4 


303. 25 

169. 50 

124. 50 
72.00 


17. 83 




24.21 

20.75 
18.00 




Total 








34 


669. 25 



















time spent in fruit during June for both localities days.. 19.68 

During 1905, at the insectary in Washington, data were obtained 
on the length of time spent in the egg and larval stages in the fruit 
for miscellaneous lots during May and June. As in the case of egg- 
hatching records, these were obtained under the same conditions in 
the insectary, where the temperature was higher than normal. These 
records are given in Table XXVII. 



LIFE HISTORY AND HABITS : THE LARVA. 



67 



Table XXVII. — Length of time spent by the plum curculio in fruit (egg and larval stages 
combined), Washington, D. C, 1905. 



Eggs 
de- 
pos- 


Date of 
deposition. 


Larva? emerged. 


Approx- 
imate 
time in 


Total 
number 
of larvpe 
devel- 
oped. 


Total 
number 

of egg 
and lar- 
val days. 


Average 
number 
of days 


Host 
fruit. 






ited. 




Number. 


Date. 


fruit. 


in fruit. 












Days. 














f 2 


May 23 


11.50 


1 












2 


May 24 


12.50 










(?) 


May 12 


I 2 

3 

I 6 

f 2 


May 25 
May 26 
Mav 27 
May 30 


13.50 
14.50 
15.50 
15.00 


1 15 
1 


211.50 


14.10 


Plum. 


7 


May 15 


I 


May 31 
June 1 


16.00 
17.00 


7 


112.00 


16.00 


Do. 


1 


Mav 16 


1 


June 2 


16.75 


1 


16.75 


16.75 


Do. 




May 16-17 


3 
f 1 


June 3 
June 1 


17.50 
14.75 


3 
1 


52.50 


17.50 


Do. 




May 16-18 


1 8 


June 2 
June 3-6 


16.00 
19.00 


\ 30 


523.75 


17.46 


(?) 


9 


May 18-19 


{ I 


June 3 
June 7 


15.50 
19.50 


} s 


85.50 


17.10 


/Plum. 
1 Do. 


5 


May 19 


5 
f " 16 


June 6 

June 5-6 


17.75 
15.00 


5 
1 


8S.75 


17.75 


Do. 


(?) 


May 20-23 


I 

\ 6 


June 7 
June 8 
June 6 


16. 25 
17.25 
12.75 


\ 25 
1 


388. 25 


15.53 


Do. 


(?) 


May 23-25 


1 8 

! i 


June 7 
June 10 
June 6 


14.00 
16.75 
13.50 


\ 38 

| 


554. 75 


14.60 


Apple. 


16 


May 23-24 


June 7 


14.75 


10 


157. 00 


15.70 


Plum. 






I 6 


June 9 


16.75 


1 












1 


June- 7 


13. 50 


1 








14 


May 24-25 


1 I 


June 9 

June 10 


15.50 
16.50 


1 12 


188. 00 


15. 67 


Do. 


9 


May 25-26 


5 


...do 


15.50 


5 


77.50 


15.50 


Apple. 


9 


May 25-27 
Total 


{ I 

ind averag 


June 7 
June 8 

e 


13.00 
14.00 


} ' 


93.00 


13.29 


Plum. 


163 


2,549.25 


15. 64 




19.25 


f 4 


June 26 


1 






15 


June 6-7 


8 
I 3 


June 27 


20.25 


15 


308. 75 


20.58 


Apple. 






June 30 


23.25 


1 










June 9-10 


4 


June 24 


14.25 


4 


57.00 


14.25 


Plum. 


7 


June 10 


2 
f 1 


June 21 
June 25 


10.50 
12.25 


2 
1 


21.00 


10.50 


Do. 


24 


June 11-13 


J 

I 15 


June 26 
June 29 
July 1 


13.75 
16.75 
18.75 


1 " 


374. 25 


17.82 


Apple. 


13 


June 10-13 


< ! 


June 27 
June 28 


15.00 
15.50 


} " 


166.00 


15. 09 


Do. 


20 


June 14 


{ ". 


June 29 
June 30 


14.75 
15.75 


> » 


273. 50 


15.19 


Do. 


10 


June 14-15 


{ ! 


June 28 
July 1 


13.25 
16.50 


} ■ 


129.00 


14.33 


Do. 


2 


June 17 
Total 
Total for sea 


2 


July 4 


17.00 


2 


34.00 


17.00 


Do. 


and averaj 


;e 


82 


1,363.50 


16.62 






son 


245 


3,912.75 











Average time spent in fruit for season, days 15.99 

The records show a range for combined egg and larval stages of 
from 10^ to 23^ days, with the average for the season of 15.99 days. 
The total number of larvae under observation was 245 and the sum 
of egg and larval days was. 3,912.75. 

Observations made at Myrtle, Ga., during 1906, on miscellaneous 
lots of eggs and larvae in peaches, during April, May, and June, are 
detailed in Table XXVIII. 



68 



THE PLUM CURCTJLIO. 



Table XXVIII. — Length of time spent in fruit by the plum curculio (egg and larval stages 
combined), Myrtle, Ga., 1906. 



Eggs 
de- 
pos- 
ited. 


Date of 
egg depo- 
sition. 


Mature 
larvse 
devel- 
oped. 


Larvse leaving fruit in specified days from deposition of eggs. 


Total 
egg 

and 
larval 
days in 
fruit. 


11 


12 


13 


14 


15 


16 


17 


1 
18 19 


20 


21 


22 


23 


24 


25 


26 


27 


2S 


29 


30 


9 
21 
(?) 
(?) 
(?) 

15 

14 

7 

12 

13 

6 

7 

14 

16 

16 

14 

12 

11 

20 

11 

8 

5 

4 

7 

5 

10 
6 
13 


Apr. 19 
Apr. 21 
Apr. 23 
Apr. 26 
Apr. 27 

Total. 

May 1 
May 7 
May 8 
May 9 
May 10 
May 11 
May 13 
May 14 
May 15 
May 16 
May 17 
May 18 
Mav IP 
May 20 
May 21 
May 22 
May 23 
May 24 
May 25 
May 26 

Total. 

June 2 
June 8 
June 17 

Total. 


4 
4 
3 

7 
5 








3 




1 




































2 


2 
2 


































1 




































3 




i 


2 


3 


1 


































1 














1 






































23 






3 


4 




2 


4 


4 j 3 


1 




1 














1 




395 
















10 
11 
7 
7 
8 
4 
3 
7 
6 
10 
9 
6 
6 
6 
6 
3 
2 














5 
4 
2 
2 
3 
2 
1 
2 






4 


1 




1 
























1 


3 

"2" 
1 

T 


1 
4 
1 

"i" 
1 
1 
1 

2 
2 


2 
1 

2 


























































2 


1 . 
























1 


"i" 
2 


1 






1 














































1 
1 


3" 
3 

"i" 




























































1 


2 
3 




























1 
2 


T 


1 


2 






















1 






2 
1 
1 


























1 
2 

~2 
1 
1 






















2 
2 

"i" 






1 




























1 
1 


1 
1 
1 








1 








1 






















1 










1 


















































1 










2 
1 
2 














1 




1 
































1 

1 




























... 










1 




































































116 | 1 
4 






5 

2 

2 


8 
1 


9 29 

... 1 


16 


17 


7 


11 


5 


2 
1 


= 


1 


2 






1 


1 


2,112 


= 


IT 

l 


= 


= 


3 
9 


































4 


... 3 






























— 


































16 




2 


4 


5 


... 4 












1 
















248 






























Total for 
April, May, 


155 


1 




5 13 


13 


11 27 


20 


20 


8 


11 


6 


3 




1 


2 






2 


1 


2,755 



















Average time in fruit for April days.. 17.17 

Average time in fruit for May do 18.21 

Average time in fruit for June do 16. 13 

Average time in fruit for April, May, and June do 17. 81 

A total of 155 larvse emerged, the time spent in the fruit varying 
from 11 to 30 days, with an average for the period of 17.81 days. 

Table XXIX gives observations on 411 larvse reaching maturity 
during May, June, and July, at Siloam Springs, Ark., in 1908. The 
fruit used was peach. 



LIFE HISTORY AND HABITS: THE LARVA. 



69 



Table XXIX. — Length of time spent in fruit by the -plum curculio (egg and larval stages 
combined), Siloam Springs, Ark., 1908. 



Eggs 
de- 
pos- 
ited. 


Date of 
egg depo- 
sition. 


Mature 
larvse 
devel- 
oped. 


Larvae leaving fruit in specified days from deposition 
of eggs. 


Total 
egg 
and 

larval 
days in 

fruit. 


15 


16 


17 


18 


19 


20 


21 


22 


23 


24 


25 


26 


27 


28 


20 


30 


8 

6 

10 

38 
56 
39 
30 
10 
8 
16 
10 
16 
16 
7 
9 
9 
7 
8 

10 
11 
16 
17 
9 

10 

5 

5 

7 

11 

12 

8 

5 

7 

11 

10 

10 

5 
3 
4 
4 
2 
2 
3 


May 12 
May 13 
May 14 
May 15 
May 16 
May ■ 17 
May 18 
May 19 
May 20 
May 21 
May 22 
May ' 23 
May 24 
May 25 
May 28 
May 29 
May 30 
May 31 

Total. 

June 2 
June 3 
June 4 
June 5 
June 6 
June 7 
June 10 
June 11 
June 14 
June 15 
June 16 
June 17 
June 19 
June 20 
June 22 
June 25 
June 27 

Total. 

July 7 
July 13 
July 15 
July 17 
July 22 
July 24 
July 26 

Total. 


6 
6 

8. 
35 
52 
37 
28 

6 

5 
16 

6 
13 

6 

6 

8 

8 

7 

7 












1 
1 
2 

21 
31 
10 


i 

10 
15 

20 


2 
1 
2 
3 
1 
4 
9 


1 
3 


2 
1 
















































3 




























1 
1 
2 
5 






















4 


























1 

8 


"i" 

2 
























1 


3 


1 








T 


2 
3 


3 

1 
3 


... 1 


















1 

1 
1 
2 


T 

"2" 


1 
















1 


1 
3 
1 


5 
"4" 


















2 

3 


1 
"i" 


Y 


1 
















1 


2 






























2 


2 
3 


... 


2 
3 
5 




















2" 
3 
1 


1 








1 














1 
























2 
1 


1 


... 
1 
1 


















1 




1 


2 


























260 


1 


7 


13 


3 


24 


SI J52 


27 21 


11 


12 


4 | 3 


1 |... 




5,424 


8 
10 
14 
14 
9 
9 
5 
4 
7 
10 
8 
7 
4 
6 
10 
6 
6 














4 


2 
1 
1 

2 

1 
1 
2 

2 
1 
2 
3 

1 


"4" 
"3" 


2 
4 
1 
3 


.. L 






















1 


















2 


7 
1 
2 
3 


2 

h' 

1 

1 
1 
1 


1 

4 

"4 
2 

T 




















1 






































... 


1 
















































1 
"2 




























1 
2 
1 
2 


"2 


2 


2 
















1 








































2 


1 
1 

2 
1 
.1 


1 
2 




























1 












1 


1 


T 


1 
4 


2 
3 

1 


"2" 








































2 
1 






















2 


1 




1 


























137 








3 


14 


15 


22 


25 


16 


19 


9 


7 


5 




1 


1 


3,057 








3 
2 
3 
2 
1 
2 
1 
















1 


1 


1 






























1 
1 

1 




1 




























2 




























1 
























1 


























1 


1 


































1 


















































14 










1 


1 


1 


1 


2 


3 


3 1 


1 








328 


















To 
J 
J 


,al for May, 
une, and 
uly 


411 


1 


7 13 


6 


39 


97 


75 


53 


39 


33 


24 


12 


9 


1 


1 


1 


8.S09 



Average time in fruit for May „ days.. 20.86 

Average time in fruit for June .' do 22.31 

Average time in fruit for July do 23.43 

Average time in fruit for May, June, and July do 21.43 



70 



THE PLUM CURCULIO. 



A total of 411 larvae was under observation, the time spent in the 
fruit varying from 15 to 30 days. The average of all individuals 
was 21.43 days. 

Observations were also, made at Douglas, Mich., during 1910 by 
Mr. Hammar, on the complete life-cycle period of 121 individuals. 
For purposes of comparison the egg and larval stages combined are 
shown in Table XXX. The fruit used was peach. The average 
time for all individuals for June and July was 20.8 days. 

Table XXX. — Length, of time spent in fruit by the plum curculio (egg and larval stages 
combined), Douglas, Mich., 1910. 



F-ggs 
depos- 
ited. 


Date of 
egg deposi- 
tion. 


Larvse leaving fruit in specified days from deposi- 
tion of eggs. 


Total 
egg and 
larval 
days in 
fruit. 


16 


17 


IS 


19 


20 


21 


22 


23 


24 


25 


26 


27 


6 
10 
4 


June 24 
June 29 
June 30 










1 
2 
1 


1 


1 




3 










3 




2 
1 


3 
2 














































Total 


3 




3 


5 

1 
3 


4 

22 

"~4 
6 


1 

"h 

8 
10 


1 

5 

7 
7 


8 
3 


3 
2 








392 


38 
20 
19 
16 

6 

1 

1 

1 


July 1 
July 2 
July 3 
July 4 
July 6 
July 20 
July 21 

'otal 











1 






















































6 




































1 
























1 


























1 

4 






10 


32 


24 


19 


11 


2 




1 


1 


2,122 








T 


1 o tal for 
June and 
July 




3 


15 


36 


25 


20 


11 


5 




1 


1 


2,514 



Average time in fruit for June : days . . 19.6 

Average time in fruit for July do 21 

Average time in fruit for June and July do 20. 8 

In Table XXXI are shown the results of observations on the length 
of time spent in the fruit by the curculio at Barnesville, Ga., during 
1910. The fruit used was peach. 



LIFE. HISTORY AND HABITS: THE LARVA. 



71 



Table XXXI. — Length of time spent in fruit by the plum curculio {egg and larval stages 
combined), Barnesville, Ga., 1910. 





Ma- 
ture 
larvae 
devel- 
oped. 


Larves leaving fruit in specified days from deposition of eggs. 


Total 


Date of egg 
deposition. 


12 


13 14 It 


16 17 18 19J20 


MM II 

21 22 23 24 25 26 27 28 29 30 31 


1 | 1 egg ana 
larval 
32 33 34 35 36 37 38 39 40 41 42 days in 
fruit. 


Apr. 8 


11 

29 
68 
4 








32 


112 1 




9 










5 2 3 11 




11 










3 12 13 2 




12 










1 




Total. 


112 








4 8 26 20 23| 


9472242 


. 1 3,465 




= = 


= = = 


= = = = = 


1~ir.7.7.7.7. 


May 9 


5 
8 

13 
1 
1 
1 
1 

15 
2 
1 

16 




10 






2 


4 2' 






12 






3 6 


. 4 






13 








1 






17 






.. 1 








18 






.... 1 .. .. 








19 




. .. 1 










21 






7 8 


. .. .. 1 






23 






..11.. .. 









25 














26 




. 14 2 




1 
















Total. 


64 


l . 


. 14 3 
. 1 .. 


810 2 3 8 


9 7 








=========== 


========== 




June 16 


1 

1 
3 
2 
2 
3 
3 
5 
3 
5 
3 




17 


. 1 .. 










18 


. 2 1 
. 1 .. 










20 




1 






22 


. 1 .. 
. 1 1 
. 1 1 
1 .. .. 
. 2 .. 


1 








24 


.. 1 








25 


.. 1 








27 


1 1 1 








28 










29 


. 4 .. 
. 1 2 


1 








30 




















Total. 


31 


2 


115 5 


3 3 1 


1 




463 


July 1 


1 
3 

4 

14 

11 

25 

8 

11 

7 

7 

7 

3 

4 

48 

45 


.. 1 


============ 







3 


2 
4 

i 


i .. 2 
2 2.. 










4 










5 


4 2 1 

5 .. 1 
7 4 2 

6 1 1 
1 2 2 
. 5 1 


5 .. .. 2 .. . 








6 


1 .. 

4 2 1.... 


1 1 .. .. 






7 


1 






8 








9 


1 .. .. 1 .. . 


. 1 1 1 .. 






12 


. .. 1 






14...... 


.. .. i .. .. 


2 .. 1 1 1 1 






15 






-.2112 


1 .. 






20 




. .. 1 


.. 1 


1 






21 




. .. 1 


11.... 1 

5 612 7 1 
9 3 3 11 








26 




. 2 6 
613 1 


22.. i i 1 1 i 






30 


3 3 11. 














Total. 


198 


73 


2 3119 


25 16 18 13 5 1 


6 4 4 2 12 111.. 




3. 309 


Aug. 7 


15 
43 
31 
2 

91 




. .. 1 


4 2 3 11 
3 6 2 3 1 
-.12.. .. 


1 .. .. 1 1 " 


= = = = = = = = = = 


- 


9 




. 1 3 


2 5 6 4 3 2 2 






10 


5 10 223231.. 






17 






.. .. 1 1 .. . 






















Total. 


93 


. 1 4 

3 61 31 


7 9 8 5 2 
43 38 29 21 15 2 


S 15J 8 7 7 4 5 1 




1.910 


Total 
for 
sea- 
son. 


496 


7 28 12 12 9 5 1110 27 21 23 
1 1 I 1 


9 4 7 2 2 4 2.. 


1 10, 282 



Average time in fruit for April riavs qn c 

Average time in fruit for May do 177* 

Average time in fruit for June do 14 94 

Average time in fruit for July "do""' 16' 76 

Average time in fruit for August "" do 20 99 

Average for the season ..7..... do 20! 73 

The Barnesville records include observations on 496 larvae, the 
period in fruit varying from 12 to 42 days. The average for the 
season was 20.73 days. 



12 



THE PLUM CURCULIO. 



In Table XXXII are brought together from the preceding tables 
the totals showing the time spent in the fruit at the several localities. 
The horizontal bars mark weekly periods from time of deposition 
of eggs, beginning with the second week. The percentage of the 
total number of larvae emerging weekly is also shown. From the 
Illinois, District of Columbia, and Georgia records it will be noted 
that there was a considerable emergence of larvse in the localities 
in question during the second week. This was highest in the District 
of Columbia, where almost 30 per cent of the total larvse emerged 
during the second week. In Georgia, 18.7 per cent of the larvae; 
came out during the second week in 1906, and during 1910 the pro- 
portion was 20.77 per cent. In all localities a notable majority of 
the larvse emerged during the third week, and with the exception of 
the Georgia material during 1910, emergence from the fruit was 
practically over by the close of the fourth week from deposition of eggs. 

Table XXXII. — Length of time spent in fruit by the plum curculio (egg and larval stages 

combined), all localities. 





Griggsville, 111., 
1904. 


Washington, D. C, 
1905. 


Youngstown, N. Y . , 
1905, and North 
East, Pa., 1906. 


Myrtle, Ga., 1906. 


Days. 


Larvae 
emerg- 
ing. 


Percent- 
age of 
larvae 
emerg- 
ing by 
weeks. 


Larvse 
emerg- 
ing. 


Percent- 
age of 
larvse 
emerg- 
ing by 
weeks. 


Larvse 
emerg- 
ing. 


Percent- 
age of 
larvae 
emerg- 
ing by 
weeks. 


Larvse 
emerg- 
ing. 


Percent- 
age of 
larvae 
emerg- 
ing by 
weeks. 


10 




1 1.70 

• 76. 66 

• 19. 38 

1.94 
.32 


f 2 
2 
\ 9 
\ 17 
{ 43 

r 58 

53 

14 
15 
21 
8 


1 29. 79 

■ 68. 98 

1.23 






, 


} 


11 




1 1 

\ 1 

13 

I 14 

f 6 
22 
36 
16 
14 
8 
11 

5 
2 
1 


I 


12 


2 
2 

17 

42 
73 
137 
210 
219 
179 
89 

77 
45 
38 
27 
22 
23 
8 

7 
9 
3 
1 
1 
1 
2 

1 


} 18. 70 


13 




• 79. 41 

• 20. 59 




14 


J 


15 




16 






17 






18 


21 


| 72.95 


19 




20 






21 


. 6 




22 .... 






23 


3 






24 


7 




25 


1 


1 6.45 


26 






2 




27 








28 










29 






f 2 
1 




30 




31.. 




32 




[ 1.90 


33 














34 






35 






36 






37... 




38 .. 






39 


1 




40 














41 

42 


1 

1 








Total 


1,238 


100. 00 


245 


100. 00 


34 


100. 00 


155 


100. 00 



LIFE. HISTORY AND HABITS : THE PUPA. 



73 



Table XXXII.— Length of time spent in fruit by the plum curculio (egg and larval stages 
combined), all localities — Continued. 





Siloam Springs, Ark., 
1908. 


Douglas, Mich., 1910. 


Barnesville, Ga.,1910. 


Days. 


Larvae 
emerging. 


Percentage 
of larvae 
emerging 
by weeks. 


Larvae 

emerging. 


Percentage 
of larvae 
emerging 
by 'weeks. 


Larvae 
emerging. 


Percentage 
of larvae 
emerging 
by weeks. 


10 


























12 










9 

33 
61 

f 31 
43 
38 
29 
21 
15 

f 28 
12 
12 
9 
5 
11 
10 

27 

21 

23 

9 

4 
7 
2 

2 
4 
2 


1 20. 77 


13 












14 












15 


1 

7 
13 

6 
39 
97 
75 

53 
39 
33 
24 
12 

9 

1 

1 

r- 


57. 91 

41. 60 

.49 




68. 60 
31.40 




16 


4 




17 




18 


3 

15 
36 
25 

f 20 
11 
5 


I 41. 13 


19 




20 




21 




22 




23 




24 




25 


I 17.54 


26 


1 
1 




27 




28 




29 






30 




31 . 




32 




1 18. 75 


33 










34 






35 . 






36 






37 












38 






















I LSI 


40 












41 












42 










1 














Total 


411 


100. 00 


121 


100. 00 


496 1 100.00 









THE PUPA. 



LENGTH OF TIME SPENT IN SOIL. 

Considerable information has been obtained on the length of time 
spent by the curculio after entering the soil for pupation until the 
emergence of the beetle. As in the case of the statistics showing the 
length of time occupied in the egg and larval stages in the fruit, the 
present data have been obtained, often from miscellaneous collections 
of infested fruit, and at irregular intervals. Records are also given 
from collections where the complementary data Were not obtained, 
or during another season. 



U 



THE PLUM CUECULIO. 



Table XXXIII gives data on time spent in the ground by the cur- 
culio at Youngstown, N. Y., during 1906. A total of 826 larvae were 
under observation, and the average time in soil for all beetles emerg- 
ing was 31.04 days, varying from 19 to 54 days. 

Table XXXIII. — Length of time spent in soil by the plum curculio, Youngstown, 

N. Y., 1905. 









Lar- 
vae. 


Adults emerging in specified days from time of entering soil by larvae. 


Date larvae entered soil. 


19 


20 


21 


22 


23 


24 


25 


26 


27 


28 


29 


30 


31 


32 


33 


34 




40 
55 
250 


















1 
"9 


2 
2 
13 


1 

"9 


2 
5 
5 


3 
5 
11 


5 

1 

19 


1 
2 
11 


9 


28 












2 


"i 


2 

5 


1 


29 


2 










3 
















Total 


345 


2 










?, 


1 

3 

1 


7 


10 

7 
3 


17 
9 

"ili 

5 


10 

10 
4 
3 
2 


12 

11 
2 
6 
3 


19 

16 
3 
2 
3 


25 

~~8~ 
3 


14 

7 
6 
8 


13 














July 1 


150 

12(3 
135 
70 






7 


2 














4 


3 














2 


7 








2 




2 


2 




5 


















Total. 


4S1 








2 
2 




2 
4 


6 

7 


7 


15 
25 


27 
44 


19 
29 


22 
34 


24 
43 


11 
36 


21 
35 


13 












Total for seas 




826 


2 


26 










Date larvae en- 


Adults 


emerging in specified days from time of entering soil by larvae. 


Total 
idults 


Total 
days 


tered soil. 


35 


3G 


37 


38 


39 


40 


41 


42 


43 


44 


45 


46 


47 


48 


49 


54 


spent 
in soil. 




3 


3 






1 
1 




1 










1 






1 




34 
21 
96 




28 




















29 


1 




4 


1 


1 


1 












































Total 


4 


3 


4 


1 

2 
1 


2 


1 


2 










1 






1 


1 


151 


4,711 


















July 1 


...1 5 

....\ 2 

1 .... 


78 
38 
39 
25 




2 




2 


1 


Y 

i 


1 


















3 






















7 






























































Total 




2 


1 


3 


1 | 7 


2 


1 
















1 


180 


5,565 






















Total for sea- 


4 


5 


5 


4 


3 


S 


4 


1 








1 






1 


1 


331 


10.276 



















Average time spent in the ground during June days. . 31. 20 

Average time spent in the ground during July do 30. 92 

Average time spent in the ground during season do 31. 04 

Table XXXIV shows similarly the time spent in the soil by curcu- 
lios from miscellaneous collections at Myrtle, Ga., in 1906. A total 
of 459 larva? entered the soil, yielding 376 adults. The average time 
in the soil of all beetles was 25.95 days, the range being from 16 to 
46 days. 



LIFE HISTORY AND HABITS: THE PUPA. *75 

Table XXXIV. — Length of time spent in the soil by the plum curculio, Myrtle, Ga., 1906. 



Date larvae entered soil. 


Larvae. 


Adults emerging in specified clays from time of entering soil 
by larvae. 




16 


17 


18 


19 


20 


21 


22 


23 


24 


25 


26 


27 


28 29 


May 17... 


63 
30 
36 
40 
. 71 
4 
















1 






8 


5 


10 8 


19 














1 








20 
























2 


1? 


25 














3 
5 


1 
13 


18 
12 
4 


1 
13 








27 . 












2 


6 


3 


8 




31 










































Total 


244 












2 


9 


15 


34 


14 
4 


14 

14 
2 


8 
14 


20 
6 


?,0 


















43 
32 














?, 


16... 


2 


3 






8 


7 






9 




















Total 


75 


2 


3 






8 


7 






9 
43 
19 


4 
18 

17 


16 

30 
10 


14 

22 
7 


6 

26 

8 


2 















Total for May and June 

Miscellaneous laboratory records 
from May 1 to July 7 


319 

140 


2 
1 


3 
1 






8 
4 


9 
4 


9 
11 


15 
19 


9? 


3 


6 


2 




459 


3 


4 


3 


6 


12 


13 


20 


34 


62 


35 


46 


29 


34 


?4 







Date larvae entered soil. 


Adults emerging in specified days from time of entering soil 
by larvae. 


Total 
adults. 


Total 
days 
spent 




30 


31 


32 


33 


34 


35 


36 


37 


38 


39 


40 


42 


45 


46 


in 
soil. 


May 17. 


2 


4 


2 


1 




















41 
2 
27 
23 
67 
5 




19. 




1 


i 


















20. 


4 


5 


4 


■ 






















25 
























27. 








2 i 








2 














31 














1 




















1 




















Total 


6 


9 


6 


2 | 3 








2 


1 










165 


4,405 


























| 




















40 
31 




16 




























































Total 






























71 


1,726 
































Total for May and 


6 
1 


9 
1 


6 

2 


2 
3 


3 
2 








2 


1 
4 










236 
140 


6,131 


Miscellaneous laboratory 
records from May 1 to 
July 7 


2 


1 


1 


1 


1 


2 


1 


3,621 








Total for season 


7 


10 


8 


5 


5 


2 


1 


1 


2 


5 


1 


1 


2 


1 


376 


9,752 



Average time spent in the ground during May days. . 26. 67 

Average time spent in the ground during June do 24. 30 

Average time spent in the ground during May and June do 25. 98 

Average time spent in the ground for season do 25. 95 

A few records were obtained by Mr. Girault at New Richmond, 
Ohio, during 1907. The 75 beetles emerging requiring an average of 
22.21 days. Data for the month of June only were obtained, and the 
variation in time occupied by individuals is comparatively small, 
from 18 to 26 days. (See Table XXXV.) 



76 



THE PLUM CUECULIO. 



Table XXXV. — Length of time spent in the soil by the plum curculio, New Richmond, 

Ohio, 1907. 



Date larvee entered soil. 


Larvae. 


Adults emerging in specified days from 
time of entering soil by larvse. 


Total 
adults. 


Total 
days 
spent 




18 


19 


20 


21 


22 


23 


24 


25 


26 


m 
soil. 




30 
20 
20 
23 




1 


~Y 

2 
2 


1 
5 
4 



2 
3 
3 
3 


9 
2 

2 
1 


8 
2 


4 
1 


4 
1 


29 
17 
11 
18 




15 




17 








IS 


2 


4 




















Total 


93 


2 


5 


7 


16 


11 


14 


10 


5 


5 


75 


1,666 







Average time spent in the soil days.. 22.21 

The records from Siloani Springs, Ark., are fairly extensive and 
cover the three months, May, June, and July. (See Table XXXV.) 
A total of 5,860 larvae was used, yielding 1,774 adults. The range for 
the various beetles is from 19 to 47 days, with an average for all of 
29 days. In this and other tables on the length of time spent in the 
ground, and also on the time spent in the fruit, the monthly totals 
and averages shown are largely arbitrary, in that the month is based 
upon the time of larvse emerging from the fruit. Larvse leaving the 
fruit in late May, for instance, would be in the ground during much 
of June. 

Table XXXVI. — Length of time spent in the soil by the plum- curculio, Siloam Springs, 

Ark., 1908. 



Date larvse entered soil. 


Larvae. 


Adults emerging in specified days from time of entering soil by 
larvse. 




19 


20 


21 


22 


23 


24 


25 


26 


27 


28 


29 


30 


31 


32 


33 




328 
574 
965 
550 
629 
719 




















1 
12 

8 
12 
54 
11 


3 

11 
11 
2 
02 
54 

143 


To" 

17 
37- 
14 
30 

108 


1 
13 

14 
17 
2 
9 

56 


5 
23 

2 
21 
32 

83 


4 


18 














2 


1 


3 

4 

10 

47 

23 


14 


21. 














16 


24. . 














1 

5 
21 


3 

"31" 


? 


27. 










2 


1 


16 


30. 










7 


















Total 


3,765 










2 


1 


29 


35 


87 


98 


59 


















June 2 


532 

449 
270 
124 
107 
81 
01 
42 
39 










8 
2 


23 

10 

2 

1 

1 

"2 


9 
9 

18 

"l2" 
6 
7 
3 


86 
14 
10 
9 
5 
9 
3 
6 
1 


38 
29 
6 
1 
6 
3 

19 
6 
2 


23 
38 
2 
1 
25 
2 
3 
6 

4 


21 
12 
23 


36 
2 


25 


4 
2 
2 
1 


1 


5 






1 






8... 






1 


11... 








1 


"5" 

2 




13 


2 


14... 






1 


1 
1 

"Y 
4 


5 
4 
1 




17 






14 


2 


1 


20 












23 .. 












3 
1 






2G.... 








1 




1 


















Total 


1,705 

146 

119 

74 

51 






2 

6 
1 
3 


2 

33 
3 
3 


17 

8 

17 

7 

1 


40 

4 
12 
3 
2 


64 

3 
5 
3 


143 

14 
6 
1 


110 

7 
3 


104 

4 
6 


63 

1 

2 

2 


48 

3 
1 


56 
2 
"2 


11 

1 
1 
1 


5 


July 22 






1 


25 


1 


1 




28 




31 








1 






























Total 


390 


1 


1 


10 


39 


33 


21 


11 


21 


10 


11 


5 


4 


4 


3 
97 


1 






Total for season 


5,860 


1 


1 


12 


41 


52 


62 


104 


199 


207 


213 


211 


160 


116 


65 



LIFE HISTORY AND HABITS I THE PUPA. 



77 



Table XXXVI.— Length of time spent in the soil by the plum curculio, Siloam Springs, 

Ark., 1908— Continued. 





Adults emerging in specified days from time of entering soil 
by larvee. 


Total 
adults. 


Total 
days 
spent 




34 


35 


36 


37 


38 


39 


40 


41 


42 


43 


44, 


45 


46 


47 


111 
soil. 




2 
12 
29 

3 
14 

06 


14 
1 

17 
3 

"2 

37 


6 
6 
1 

1 

1 
22 


11 
.... 

4 




2 

4 

.... 

5 


2 
1 
4 
2 


3 1 


1 








1 


2 


50 
124 
131 
123 
253 
211 












1 
1 


1 




21 










1 


2 






5 












1 
1 


.... 


1 


1 












1 


























Total 


18 


14 


in 


8 


3 


2 


1 


3 


1 


2 


4 


892 


27,470 


















Juno 




10 
.... 




1 


4 


1 


1 


1 1- 










293 
124 
71 
31 
49 
50 
34 
29 
19 




5 


4 
1 
2 


1 
1 














8 


2 


2 








1 












11 
























































































































































1 




1 


















































7 


12 


2 


3 


3 
1 


4 
"i" 


1 


1 


1 


1 










700 


19, 434 
















1 
















89 

62 

27 

4 






1 






1 
1 


















28 


1 
















































1 
74 


1 

50 


24 


2 
23 
























Total 


1 

18 


1 

15 


1 
10 
















182 


4,547 




4 


3 


2 


3 


1 








Total for season 


2 


4 


1,774 51,451 



Average time spent in the ground during May.. days. . 30. 79 

Average time spent in the ground during June do 27. 76 

Average time spent in the ground during July '. do 24. 93 

Average time spent in the ground for season do 29. 00 

Data on time spent in ground in Washington, D. C, were obtained 
by Mr. Jones during 1908. A total of 1,114 adults was reared from 
5,956 larvae entering the soil, the range for individuals being from 18 
to 56 days, with an average of 31.09 days for the season. (See Table 
XXXVII.) 

Table XXXVII. — Length of time spent in the soil by the plum curculio, Washington, 

I). C. 



Dates larvse entered soil. 


Larvae. 


Adults emerging in specified days from time of entering soil by 
larvse. 




18 


19 


20 


21 


22 


23 


24 


25 


26 


27 


28 


29 


30 

2 
2 
2 
2 

8 

7 
5 
3 
1 
4 


31 

1 
12 

4 
6 

23 

4 
8 

y 

2 


32 

5 

4 
17 
6 

32 

15 
4 
1 


33 

8 
5 
1 

7 

21 

18 
9 


34 
3 

27 
1 
1 

32 

8 
2 


35 

7 
13 
4 

24 

1 
3 


36 




187 
283 
218 

297 














11 


28 






















3 


4 
3 


7 


30 






















fi 


31 
























1 


























7 

4 
1 
5 






985 

2S1 
206 
162 
90 
174 
243 
208 
223 
157 
154 
249 




















3 


9A 




— 


— 


— 


— 


— 


— 


— 


— 


— 


1 




o 














































1 


4 




















1 






1 
3 
1 


5 
1- 


3 






















1 


1 
































7 




























1 
1 

7 
1 
1 






























1 
1 
1 
1 


"i" 


3 
4 
3 


2 
3 
2 

2 












9 
















1 




5 
"3 


"i" 


4 
2 
2 


3 


2 


10 . 


1 




1 












11.... 

















78 



THE PLUM CUBCULIO. 



Table XXXVII. 



-Length of time spent in the soil by the plum curculio, Washington, 
B.C., 1 90S— Continued. 



Dates larvse entered sol 


. 


Larvse. 


Adults emerging in specified days from time of entering soil by 
larvse. 






18 


19 


20 


21 


22 


23 


24 


25 


26 


27 


28 


29 


30 


31 


32 


33 


34 


3.3 


36 


June 1? 


309 

172 

190 

140 

296 

107 

60 

122 

106 

139 

175 

177 

64 

148 

97 

61 

24 

51 






1 


"i" 


2 


2 
2 


1 

3 

1 
1 

3 


2 

9 
2 

6 

"i 

2 
3 
5 


4 
9 

12 

4 
4 
9 
1 

3* 
2 
9 
6 


8 
12 
3 

2 
6 

2 
10 

1 
2 
5 
4. 

"e" 

is 


4 
1 

2 
2 
4 
9 
1 

"5" 

2 

1 
4 

T 

1 


11 
10 

8 

1 

6 

4 

2 

6 

1 

1 

3 

1 

i 

"i 


10 

2 

2 
3 
9 
2 

1 
1 
5 
3 

1 

2 
2 


7 
8 
12 

14 

2 
2 
1 

3 


3 

9 

"2 


13 
3 
8 

4 
2 

1 

1 
1 


4 

3 
1 

4" 


-1 

1 
6 

"3" 




13 




14 




15 : 




16 

17 


3 


18 


1 


19 




20 




21 








29 








24 

25 


1 
1 

1 


2 


1 


2 




26 




27... 


...1... 










28 


1 








29 








30 .. 














Total..' 


4,645 

47 
42 
34 
24 
27 
16 
34 
28 
39 
10 
i 11 


1 


2 


i 


2 
1 


4 

1 
1 

Y 
i 


15 

2 
3 

T 
1 
1 


31 

2 
5 
1 
1 

5 


63 

2 

4 

1 

3 

. 2 

. "i" 


80 
3 

3 

6 


3S 
2 

4 
1 


83 

1 

2 

2 

1 
2 


72 

2 

1 


81 
1 

1 


46 


65 


36 


29 


10 


July 1 






2 




3 




4 




i 




1 








5 




6 






1 






8... 






9 




2 












10 




11 




13 


6 

i8 ... 




14 








Total 


326 




2 


i 


1 


4 


8 


14 


13 


12 


7 


8 
98 


3 

83 


2 
106 


78 


1 

87 


1 

C9 








53 




Total for season. 




5,956 


1 





4 


2 


3 


8 


23 


45 


76 


92 148 


34 




1 1 




Dates larvse entered 
soil. 


Adults emerging in specified days from time of entering soil by 
larvse. 


Total 
adults, 
in soil. 


Total 

days 


37 


38 


39 


40 


41 


42 


43 


44 


45 


46 


47 


48 


49 


50 


51 


52 


53 


54 


56 


in s 


Ml. 


May 27 


3 

12 


11 

14 

1 


15 
1 


3 


3 


1 


3 


1 


2 


1. 






2 




1 


1 






2 


85 
103 
38 
25 




28 








31 












Total 


15 


26 


16 


3 


3 


1 


3 


1 


2 


1 




2 




1 


1 






2 


251 


8,823 


June 1 


1 




5 


2 






2 


8 


1 
1 

1 


1 

1 

1 
1 


1 




2 




3 




1 




71 
37 

24 

20 

4 

7 

5 

37 

18 

14 

84 

84 

42 

6 

52 

19 

20 

39 

31 

18 

29 




2 






1 
1 






1 




2 




4 




5 


1 
1 


1 
2 




6 










7 




1 
4 








2 
1 

1 


1 


1 
1 




8 


1 
2 




9 






10 






11 


1 


1 
9 
1 


3 

17 


7 
8 
3 


4 
1 




1 

■ 1 

1 . 




12 




13 






14 






15 






16 


3 


1 
1 


1 
















17 










19 




20 






...... 













LIFE HISTORY AND HABITS : THE PUPA. 



79 



Table XXXVII. — Length of time spent in the soil by the plum curculio, Washington, 

D. C, 1908— Continued. 



Dates larvae entered 
soil. 


Adults emerging in specified days from time of entering soil by 
larvae. 


Total 
adults. 


Total 

days 

spent 

in soil. 


37 


38 


39 


40 


41 


42 


43 


44 


45 


46 


47 


48 


49 


50 


51 


52 


53 


54 56 


in soil. 


June 24 






































11 




25 






































13 
5 

14 
31 
14 




26" 








































27 








































28 






































29 




































30 






1 




























21 




































Total 


10 


IS 


26 21 


5 


6 


3 


10 i 3 


4 


3 


3 


_ 1 2 




3 


... 1 ... 777 


24, 354 






July 1 














1 




















8 
2 
14 
9 

6 
22 
11 
3 
2 
2 




2 






































3 






































4 






1 
































5 






































6 






I 
































7 












2 
























8 








2 




1 


























9 
































10 




1 






1 


























13 


1 


i 




























































Total 


1 

26 


1 
45 


1 2 


S 


2 

9 


2 

8 




















86 


2,390 






5 


3 


3 




1 


4 





1 | 2 




Total for season 


43 


26 


11 


5 


2 


2 


1,114 


35, 567 



1 No beetles emerged. 

Average time spent in the soil during May days. . 35. 15 

Average time spent in the soil during June do 31.34 

Average time spent in the soil during July do 27. 78 

Average time spen t in the soil for season ." do 31. 09 

Data obtained by Mr. Hammar at Douglas, Mich., during 1910 are 
shown in Table XXXVIII. A decided lengthening of the period is 
evident, the range being from 27 to 58 days, with an average for all 
individuals of 36.32 days. A total of 177 adults was reared from 
207 larvae. 

Table XXXVIII. — Length of time spent in the soil by the plum curculio, Douglas, 

Mich., 1910. 



Date larvae en- 
tered soil. 


Larvae. 


Adults emerging in specified days from time of entering soil 
by larvae. 


Total 

adults. 


Total 
days 
spent 
in soil. 


27 


28 

1 

1 

2 

2 


29 

2 

2 

2 

2 

4 


30 

1 

3 

4 
4 


31 

1 

1 
3 
1 

6 

6 


32 

1 
1 

1 

2 

2 

5 
6 


33 
3 

3 
2 

1 
1 
2 
6 
1 

13 

16 


34 

1 

1 

1 
2 

4 

2 

10 
2 

21 

■ >■> 


35 

1 
1 
1 

3 

12 
3 

"i 
1 

9 
3 

29 

32 


36 

2 
3 

h 

10 
10 


37 

2 

2 

3 
3 
3 
4 
3 
1 

17 

19 


38 

2 
3 

4 
3 
2 
1 

15 
15 


39 

i 

1 
1 


40 

2 

2 
5 
3 

8 
10 


41 

2 
2 

4 
4 


42 

1 

1 

3 
2 

1 



7 


43 

2 

2 

7 

7 
9 


44 


45 

1 
- 

1 

1 


47 

1 

1 

2 


48 

2 

2 


49 

1 
1 


50 


55 
1 


5S 
1 


June 24 


6 

10 
11 


6 

10 
6 




29 




30 








Total 


27 


1 

1 
2 

2 


22 


849 


July 1 


37 

24 
19 
18 
9 
9 
42 
12 
10 


37 

19 

19 

13 

8 

8 

38 

9 

4 




2 




3 




4... 




6 

8 




13 




20 




25 








Total 


180 


2 


2 


1 




1 
1 


1 
1 


155 ! 5.5S5 


Total for 
season 


207 


177 


6.434 



Average time spent in ground during June days. . 3S. 59 

Average time spent in ground during July do 36. 03 

Average time spent in ground during season do 36. 32 



80 



THE PLUM CUECULIO. 



Table XXXIX gives details of time spent in the ground of 1,568 
individuals at Barnesville, Ga., covering the period May, June, July, 
and a part of August. A total of 2,917 larvas was used. The range 
of the different individuals is from 21 days to 62 days — the longest 
yet noted — the average being 34.44 days. 

Table XXXIX. — Length of time spent in the soil by the plum curculio, Barnesville, 

Ga., 1910. 











Adults emerging in specified days from time of entering soil by larvae. 


tered soil. 




21 


22 


23 


24 


25 26 


27 


28 


29 


30 


31 


32 


33 


34 

6 

9 

40 

22 
18 
31 


35 

5 
18 

64 
21 
29 
21 


36 

5 

16 
52 
13 

9 
35 

8 

9 
11 

5 


37 

3 

51 
37 
14 
12 
13 

2 
11 

8 


38 

4 

39 

30 

11 

10 

12 

2 

1 

5 

13 


39 

3 
13 
10 

1 

1 

3 

5 

l" 

4 


40 

2 
12 
11 
1 
5 
3 
1 
2 


41 




77 i 
457 ! 
566 
240 | 
209 ! 
272 
159 
192 1 
142 










































3 

5 
5 
3 
LI 
L9 
22 
L0 
11 
1 
1 


7 
10 
10 
15 
27 
15 
25 
14 
11 


4 


8 




















1 


3 
3 


2 


10 




















3 


11 






















2 
















1 






1 
6 
14 
9 

15 
9 


6 
9 
15 
8 
9 
3 

1 


2 


13 
















2 
8 
3 
7 
9 
2 
1 


20 1 22 




15 














1 

2 
2 
6 
2 
1 


4 
2 
1 
9 

4 
2 


17 

13 

9 

3 


10 

10 

4 

1 




18 






1 

T 
l 


2 
1 
2 
3 


1 
2 

1 

s 
4 


3 


21 


190 
66 
33 

28 


1 


1 


1 
1 
1 
1 


5 




































































Total 


2,631 


1 


1 | 4 


3 


8 16 


15 


22 J32 


35 


57 


31 


134 


188 


205 


163 


151 


127 J41 


37 


21 


T K 


28 
14 






2 

2 


1 
2 


3 3 


1 


2 
1 


2 
1 




1 


















10 








1 




















































Total 


■ 42 |--.|---| 4 


3 3 | 4 


1 


3 


3 


1 


| 

























= 






= 




= 


— 


July 4 


4 

4 

3 

36 

23 

25 

51 

27 

12 

17 

8 
































9 










































13 


















1 
2 


































2 
2 
1 
5 
1 


2 




3 


3 




2 




1 














18 








1 

2 

3 


! 




















1 
1 


1 
1 
4 
1 
1 


1 
1 

3' 

1 
1 


6 
2 
2 






1 
1 


1 

1 


"i" 

1 
1 


1 








1 


1 












1 


1 


1 




3 


28 




1 


1 


1 








1 


29 








1 
1 


























2 


~2~ 


1 


"i" 


2 
1 


1 




1 




















1 






1 






































Total 


210 




1 | 3 


8 


13 10 


7 


14 


5 


7 


3 


4 


5 


1 


3 


2 


1 


1 


1 




4 


. . 


10 
11 
13 










1 




1 
2 


1 

1 
1 












1 




















1 


1 
1 


1 1 






1 


















7 






1 




1 


























. i 


























Total 

Total for 
season.. .. 


34 

2,917 






1 


2 
16 


1 


9 1 1 


3 

42 


3 

43 


1 

63 


1 






1 

209 














1 


2 


12 


29 32 


24 


61 


96 


139 


189 


165 


152 


128 


42 


37 


25 


Date larvae en- 


Adults emerging in specified days from time of entering soil by larvae. 


Total 
adults. 


Total 
days 


tered soil. 


12 


43 


44 


45 


46 


47 


48 


49 


50 


51 


52 


53 


54 


55 


56 


57 58 


59 


6( 


) 61 


62 


spent 
in soil. 














































28 

182 

276 

105 

109 

170 

117 

145 

101 

108 

45 

21 

13 






7 
2 






1 
1 






1 


'3 


1 






























4 




1 










































1 






























I 








1 


~i 


1 






1 




1 


















1 
1 






















1 






13 






1 


1 






1 




1 












1 




15 








I 4 














1 






1 












































1 


2 








2 








































































































































































































Total 1 


2 8 




2 


5 


1 


5 


4 | 2 


1 


1 




2 




1 




1 




1 


1 1 


1,420 


49, 570 



LIFE HISTOEY AND HABITS: THE PUPA. 81 

Table XXXIX. — Length of time spent in the soil by the plum curculio, Barnesville, 

Ga., 1910 — Continued. 



Date larva en- 


Adults emerging in specified days from time of entering soil by larvse. 


Total 

adults. 


Total 

days 


tered soil. 


42 


43 


44 


45 


46 


47 


48 


49 


50 51 


52 


53 


54 


55 


56 


57 


5S 


59 60 


61 


62 


spent 
in soil. 


































| 






15 

7 




10 


















1 




























































Total 
















...L.I... 












1 i I 1 


22 


572 






















= 


... 






July 4 










i. 

















1 
15 
3 

20 
27 
14 

6 
12 

8 




9 












































13 


















. . ... 


























15 












































18 




































...I.. 




23 


1 










i 








1 




1 
1 
1 














26 


1 


...1 i 


1 




l 


1 










| 










28 . 






1 
















...... 










29 






i 








I 






















30 


i 














i 
l 
























31 




i 






























2 


1 




■- -|--- 




















Total 




1 


1 ... 


1 




3 








1 |... 


3 


| 




1 


106 


3,317 


















Aug. 1 










1 






1 




i 












1 


4 
8 
8 




3 










1 










1 1 
















7 








i 






















! 




Total 






































1 




1 






. .1... 




1 I' 












1 


20 


543 






3 




6 


4 




1 














Total for 
season.. 


14 


9 




6 


1 


5 


1 




3 


... 


4 




1 




1 


1 


1 


1,56S 


54,002 



Average time spent in the ground during May days. . 34. 91 

Average time, spent in the ground during June do 26. 00 

Average time spent in the ground during July do 31. 28 

Average time spent in the ground during August do 27. 15 

Average time spent in the ground during season do 34. 44 

Iii Table XL the totals from the foregoing tables on length of time 
spent in the soil are given for more ready comparison. The hori- 
zontal bars divide the period into weeks, beginning with the third 
week. The percentages of total adults emerging each week are also 
shown. Except in the Ohio records, which are perhaps abnormal, 
and the Georgia record for 1906, comparatively few beetles were out 
within three weeks from the time of entering the soil by the larvre. 
During the fourth and fifth weeks, however, the great majority of 
beetles appear and by the close of the sixth week emergence has 
practically ceased. 

17262°— Bull. 103—12 6 



82 THE PLUM CURCTJLIO. 

Table XL. — Length of time spent in the soil by the plum curculio; totals for all localities. 





Locality and date. 




Youngstown, N. Y., 
1905. 


New Richmond, 
Ohio, 1907. 


Douglas, Mich., 
1910. 


Washington, D. C, 
1908. 


Days in soil. 


Beetles 
emerg- 
ing. 


Percent- 
age of 
beetles 

emerging, 

by 

weeks. 


Beetles 
emerg- 
ing. 


Percent- 
age of 
beetles 

emerging, 

by 

weeks. 


Beetles 
emerg- 
ing. 


Percent- 
age of 
beetles 

emerging, 

by 

weeks. 


Beetles 
emerg- 
ing. 


Percent- 
age of 
beetles 

emerging, 

by 

weeks. 


16 




0.60 

• 26. 89 

• 62. 54 

9.07 
.60 
.30 




40. 00 
. 60. 00 










17 










18 




2 
5 

7 
16 

f 11 
14 

10 
5 
5 


1 




19 


2 


0. 63 


20 




2.26 
i 50. 85 
• 37. 29 

8.48 

.56 
.56 


4 
2 

f 3 

8 
23 

45 
76 
92 

48 

f 98 
83 
106 
78 
87 
69 
53 

f 34 
26 
45 
43 
26 
8 
9 

f 8 
11 
5 
5 
3 
3 
2 

f 2 
1 

4 




21 






22 


2 




23 






24 


4 

7 

7 

25 

44 

29 
34 
43 
36 
35 
26 
4 

5 
5 
4 
3 
8 
4 
1 






25 




I 26. 48 


26 






27 


2 
2 

f 4 

4 
6 
6 
16 
22 
32 

f 10 

19 
15 
1 
10 
4 
7 

9 




28 






29 

30 






31 




32 


[ 51.53 


33 








34 




35 




36 




37 




38 




39 


I 17. 14 


40 








41 




42 




43 




44 






45 




1 




46 


1 


\ 3.32 


47 






2 
2 
1 




48 






49 


1 




50 : 




51 








52 








53 






.90 


54 


1 








1 




55 


1 




56 




2 




57 








58. . 




1 




59 




























61 






62 












Total 


331 


100. 00 


75 


100. 00 


177 


100. 00 


1,114 


100. 00 







LIFE HISTORY AND HABITS : THE PUPA. 



83 



Table XL. — Length of time spent in the soil by the plum curculio; totals for all 

localities — Continued. 





Locality and date. 


Days in soil. 


Siloam Springs, Ark., 
1908. 


Myrtle, Ga., 1906. 


Barnesville, Ga., 1910. 




Beetles 
emerging. 


Percentage 
of beetles 
emerging, 
by weeks. 


Beetles 
emerging. 


Percentage 
of beetles 
emerging, 
by weeks. 


Beetles 
emerging. 


Percentage 
of beetles 
emerging, 
by weeks. 


16 




0.79 

49. 49 

43. 58 

5.47 

.67 


f 3 ~ 

4 
3 
6 
12 
13 

f 20 
34 
62 

45 
46 
29 
34 

f 24 
7 
10 
8 
5 
5 
2 

f 1 

1 
2 
5 
1 


10. 62 
69. 95 

15. SO 

2.85 

.78 






17 








18. . . 








19 


1 

1 

12 

41 
52 
62 
104 
199 
207 
213 

211 
160 
116 
97 
65 
74 
50 

24 
23 
18 
15 
10 
4 
3 

2 
3 
1 
2 
4 




0. 06 


20. . . 






21 


1 i 

f 2 
12 

16 
29 
32 

24 
42 

f 43 
63 
61 
96 
139 
189 
209 

f 165 
152 
128 
42 
37 
25 
14 

9 




22 




23 




24 




25... 


1 10. 01 


26. 




27. 




28. 


J 


29 




30. 




31 




32 


1 51.02 


33 




34. 




35 




36 




37 




38 




39 


I 35. 91 


40 




41. 




42 


1 
r 




43 




44 






45. 


2 

1 


3 

6 

1 
6 
4 

f 5 
1 
1 




46 


I 1.85 


47 




48 






49 








50 








51 




52 




53. 


i .89 


54 


■ 








3 




55 




56 


{ 4 




57 




58 


1 




59 






1 
1 
1 
















61 




62 








Total 


1,774 


100. 00 


386 


100. 00 


1,568 


100. 00 







LENGTH OF PUPAL STAGE, AND TIME SPENT IN SOIL BEFORE AND AFTER 

PUPATION. 

The data on the length of time spent in the soil do not show the 
length of the pupal instar, since a few days are spent by the larva in 
its cell before transforming to the pupa, and after the pupa has trans- 
formed to the adult, or beetle, a variable time is spent before the 
insect makes its escape from the ground. This latter period will vary 



84 



THE PLUM CURCULIO. 



much, depending upon the character of the weather, whether dry or 
rainy. During periods of drought beetles appear to remain in their 
cells much longer than if the earth be moist or wet, as from rains. 
In fact, in orchards it has often been observed that shortly after a 
good soaking rain beetles were soon in evidence in large numbers, 
whereas previously they had been quite scarce. 

Some data have been collected on the exact time spent in these 
three conditions in the soil and are brought together in the following 
tables. Writers appear not to have investigated this point hereto- 
fore. The data from a practical standpoint are important, since dur- 
ing the pupal stage the insect would be likely to suffer most from 
cultivations. 

Table XLI. — Length of pupal instar of the plum curculio and days spent in soil as larva, 
pupa, and adult, Washington, D. C, 1908. 



Individual No. 


Date 

larva 
left 
fruit. 


Date of 

pupation . 


Date of 
transfor- 
mation 
to adult. 


Date 

beetle 

left 

soil. 


Days in 
larval 
stage 
before 
pupa- 
tion. 


Days in 
pupal 
stage. 


Days as 
beetle 
in soil. 


Total 

days in 

soil. 


1 


June 6 
...do 


June 19 
June 18 
June 22 
June 18 
June 19 
June 18 
do.... 
June 22 
June 18 
June 19 
June 18 
June 24 
June 22 
...do 


June 27 
...do...'. 
...do.... 

...do.... 
June 29 

...do.... 
June 27 
June 29 
June 27 
June 29 

...do.... 
July 3 
June 30 

...do 


July 5 
July 6 
Died. 
July 5 
July 6 
July 8 
July 6 
July 8 
July 6 
July 5 
July 6 
July 11 

...do.... 
July 7 

...do 


13 
12 

1G 
12 
13 
12 
12 
16 
12 
13 
12 
15 
13 
13 
13 
13 
10 
14 
14 
14 
14 
14 


8 
9 
5 
9 

10 

11 

9 

7 

9 

10 
11 
9 
8 
8 
8 
9 

10 
6 
7 
8 
6 
7 


8 
9 


29 


2 


30 


3 


...do... > 




4 


...do 


8 
7 
9 
9 
9 
9 
6 
7 
8 
11 
7 
7 
5 
6 
9 


29 


5 


...do 


30 


6 


...do 


32 


7 


...do 


30 


8 


...do 


32 


9 


...do 


30 


10 


..do 


29 


11 


...do 


30 


12 


June 9 
...do 


32 


13 


32 


14 


...do 


28 


15 


...do 


...do 


...do 


28 


16 


...do 


...do 


July 1 
June 29 
...do.... 
June 30 
July 1 
June 29 
June 30 


July 
July 5 
July 8 
Died. 
July 7 

...do.... 

...do.... 


27 


17 


...do 


June 19 

June 23 

.do 


26 


18 


...do 


29 


19 


...do... 




20 


...do 


...do 

...do 


(i 
8 
7 


28 


21 


...do 


28 


22 


...do 


...do 


28 












Total 




290 


184 


155 


587 












13. 18 


8. 30 


7.75 


29.35 







From the table it will be noted that the average time spent in 
the soil before pupation for the 22 individuals is 13.18 days; the 
length of the pupal instar, 8.36 days; and the period occupied in 
the soil as a beetle before emergence, 7.75 da} r s. The average time 
spent in the ground from entrance of larvae to emergence of adult 
is 29.35 days. 

These larva? were kept in large glass vials, the soil being a sandy 
loam. Specimens were kept in an out-of-doors breeding cage in 
the insectary yard, at Washington, D. C, where the temperature 
would be somewhat higher than in the soil. 

Mr. Hammar made observations during 1910, at Douglas, Mich., 
on a large series of individuals, as detailed in Table XLII. 



LIFE HISTOEY AND HABITS: THE PUPA. 



85 



Table XLII. — Length of pupal instar of the plum curculio and time spent in the soil as 
larva and as adult, Douglas, Mich., 1910. 



Individual No. 


Date 

larva 

left the 

fruit. 


Date of 
pupation. 


Date of 
transfor- 
mation 
to beetle. 


Date 
beetle 
left the 

soil. 


Days in 
larval 
stage 
before 
pupa- 
tion. 


Days in 
pupal 
stage. 


Days as 
beetle 
in soil. 


Total 

days in 

soil. 


1 


June 30 
...do 


July 11 
July 12 
July 13 
July 21 
...do 


July 26 
July 25 
July 27 
Aug. 2 
...do 


Aug. 1 
July 29 
Aug. 2 
Aue. 7 
Aug. 8 
Aug. 5 
Aug. 8 
Aug. 3 
...do 


11 
12 
11 
19 
17 
18 
18 
11 
15 

9 
11 
12 
13 
13. 
14 
14 
14 
10 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
11 
12 
12 
12 
12 
12 
12 
12 
12 
12 
12 
12 
12 
12 
12 
12 
12 

7 
13 
13 
13 
19 
10 
10 
10 
10 
10 
12 
12 
12 
13 

9 

9 

10 
13 


15 
13 
14 
12 
12 
10 
11 
10 
9 

15 
14 
14 
11 
13 
11 
12 
12 
16 
16 
14 
15 
15 
15 
16 
14 
14 
14 
15 
15 
16 
15 
15 
11 
15 
14 
15 
15 
15 
15 
15 
14 
14 
14 
14 
15 
15 
16 
16 
15 
15 
19 
14 
15 
15 
15 
16 
16 
15 
16 
16 
14 
14 
14 
12 
14 
14 
14 
11 


6 
4 
6 
5 

6 

4 

6 

4 

4 

9 

8 

5 

9 

9 

8 
11 
13 

5 

6 

9 

9 

7 

8 

7 

9 

9 

9 

7 

8 

8 

9 

9 
11 

8 

9 

9 

9 

8 

8 

7 

4 

5 
10 

6 

7 

5 

5" 

8 

3 

8 
10 

3 

8 

3 

7 

7 

8 

S 

8 

6 

8 

8 

8 

6 

6 

5 

5 

5 


32 


2.. 


29 


3 


July . 2 
...do 


31 


4 


36 


5 


July 4 
...do 


35 


6 .... .... 


July 22 
...do 


Aug. 1 
Aug. 2 
July 30 
...do 


32 


7 


...do 


35 


8 


July 6 
...do 


July 20 
July 21 
July 17 
July 19 
July 20 
July 21 

do 

July 22 
...do 


28 


9 


28 


10 


July 8 
...do 


Aug. 1 
Aug. 2 
Aug. 3 
Aug. 1 
Aug. 3 
Aug. 2 
Aug. 3 

do.... 
Aug. 8 
Aug. 9 
Aug. 7 
Aug. 8 

do 

...do 


Aug. 10 
...do.... 
Aug. 8 
Aug. 10 
Aug. 12 
Aug. 10 
Aug. 14 
Aug. 16 
Aug. 13 
Aug. 15 
Aug. 16 
Aug. 17 
Aug. 15 
Aug. 16 

...do 

...do.... 
...do 


33 


11 


33 


12 


...do 


31 


13... 


...do 


33 


14 


...do 


35 


IS 


...do 


33 


16 


...do.... 


37 


17 




...do 


39 


18... 


July 13 
..do 


July 23 
July 24 
...do 


31 


19 .. 


33 


20 


...do 


34 


21... 


...do 


do.... 
...do 


35 


22.. 


...do 


33 


23 


...do 


...do 


34 


24 . 


...do 


...do 


Aug. 9 
Aug. 7 
...do 


34 


25 


...do 


do.... 


34 


26 


...do 


34 


27 


...do 


...do 


...do 


...do 


34 


28... 


...do 


...do 


Aug. 8 
...do 


Aug. 15 
Aug. 16 
Aug. 17 

...do 

...do 


33 


29 


...do 


...do 


34 


30 


...do 


do 

...do 


Aug. 9 
Aug. 8 
...do 


35 


31 


...do 


35 


32 


...do 


...do 


35 


33 . 


...do 


...do 


Aug. 4 
Aug. 8 

...do.... 
Aug. 9 

...do 


Aug. 15 
Aug. 16 
Aug. 17 
Aug. IS 
...do.... 


33 


34 


...do 


...do 


34 


35... 


...do 


July 25 
...do 


35 


36 


...do.... 


36 


37 


...do 


...do 


36 


38 . 


...do 


...do 


...do 


Aug. 17 
...do 


35 


39 


...do 


...do 


...do 


35 


40 


...do 


...do 


...do 


Aug. 16 
Aug. 12 
Aug. 13 
Aug. 18 
Aug. 14 
Aug. 16 
Aug. 14 
Aug. 15 
Aug. 18 
Aug. 12 
Aug. 17 
Aug. 18 
Aug. 12 
Aug. IS 
Aug. 13 
Aug. 23 
Aug. 22 
Aug. 23 
Aug. 22 
Aue. 23 
Aug. 21 
Aug. 23 
...do.... 


34 


41... 


...do 


...do 


Aug. 8 
...do 


30 


42 . 


...do 


...do 


31 


43 


...do 


...do 


...do 


36 


44 . 


...do 


...do 


...do 


32 


45 


...do 


...do 


Aug. 9 
...do 


34 


46 


...do 


...do 


32 


47 


...do 


...do 


Aug. 10 
...do 


33 


48 . 


...do 


...do 


36 


49 


...do 


do 

...do 


Aug. 9 
...do 


30 


50 


...do 


35 


51 


...do 


July 20 
July 26 
...do 


Aug. 8 
Aug. 9 
Aug. 10 
...do 


36 


52. 


...do 


30 


53 


..do 


36 


54 


...do 


...do 


31 


55 


...do 


Aug. 1 
July 30 
...do 


Aug. 16 
Aug. 15 
...do 


41 


56 


July 20 
...do 


33 


57 


34 


58 


...do 


...do 


Aug. 14 
Aug. 15 

...do.... 

...do.... 

...do 


33 


59 


...do 


do.... 

do 

Aug. 1 


34 


60 

61 


...do.... 
...do 


32 
34 


62 


...do 


34 


63 


...do 


...do 


...do 


...do.... 


34 


64. . 


...do 


Aug. 2 
Aug. 3 
...do 


Aug. 14 
Aug. 17 

do 

Aug. 18 
...do 


Aug. 20 
Aug. 23 
Aug. 22 
Aug. 23 
...do.... 


31 


65 

66 


July 25 
...do 


29 
28 


67 


...do 


Aug. 4 
Aug. 7 


29 


68 


...do 


29 












Total . . . 




818 


960 


4S5 


2, 203 












12.03 


14.12 


7.10 


33.28 







86 



THE PLUM CURCTJLIO. 



These individuals were also kept in vials under out-of-doors 
conditions. The average of the 68 examples for the time spent 
in soil previous to pupation is seen to be 12.03 days; for the pupal 
stage, 14.12 days; and an average of 7.10 days was spent in the 
soil before exit of adult, after transformation. The average of 
the total days in the soil for all stages is 33.28 days. The range 
in time in soil before pupation is from 7 to 19 days. The range 
for the pupal stage is from 9 to 19 days; and for the beetle in the 
earth, 3 to 13 days. The entire time spent in the ground varies 
from 28 to 39 days. 

Similar data from Barnesville, Ga., obtained during 1910, are 
shown in Table XLIII. Records for 38 individuals were obtained 
from May 20 to July 11, when the last beetle left the soil. The 
insects were piacecl in glass-bottomed boxes containing a shallow 
layer of sand and kept in a dark box under shade out of doors. 

Table XLIII. — Length of pupal instar of the plum curculio and time spent in the soil as 
larva and as adult,' Barnesville, Ga., 1910. 



Individual No. 


Date 

larva left 

fruit. 


Date of 
pupa- 
tion. 


Date of 
transfor- 
mation 
to beetle. 


Date 
beetle left 
the soil. 


Days in 
larval 
stage 
previous 
to pupa- 
tion. 


Days in 
pupal 
stage. 


Days as 
beetle 
in soil. 


Total 

days in 

soil. 


1 


May 20 
...do 


June 5 
June 7 
May 31 
June 3 
...do 


June 14 
June 17 
June 8 
June 13 
June 12 
June 13 
June 14 
June 15 
June 14 
June 15 
June 14 
June 16 
...do 
June 11 
June 18 
June 19 
June 21 
June 25 
June 26 
June 25 
July 3 
July 6 
...do 


June 20 
June 22 
June 14 
June 19 
June 20 

...do 

June 21 
...do 
June 20 
...do 
June 23 
June 24 
June 21 
June 20 
June 24 
June 25 
June 27 
July 1 
July 2 
June 29 
July 6 
July 11 
July 12 
July 9 
July 14 
July 9 
July 7 
...do.... 
...do.... 
July 10 

...do 

July 8 
July 11 
July 10 
...do.... 


16 
18 
11 
14 
14 
14 
15 
16 
16 
16 
16 
16 
17 
13 
IS 
19 
22 
26 
27 
13 
18 
19 
19 
20 
20 
15 
12 
12 
12 
13 
13 
13 
16 
14 
14 
14 
14 


9 

10 
8 
10 
9 
10 
10 
10 
9 

10 
9 
11 
10 
8 
10 
10 
9 
9 
9 
8 
S 
10 
9 
9 
9 
9 
8 
9 
9 
9 
9 
9 
9 
9 
9 
9 
9 


6 
5 
6 
6 
8 
7 
7 
6 
6 
5 
9 
8 
5 
9 
6 
6 
6 
6 
6 
4 
3 
5 
6 
2 
7 
5 
6 
5 
5 
6 
6 
4 
4 
4 
4 
4 
5 


31 


2 


33 


3 


...do 


25 


4 


...do 


30 


5 


...do 


31 


6 


...do 


...do.... 


31 


7 


...do 


June 4 
June 5 
...do.... 


32 


8 


...do 


32 


9 


...do 


31 


10 


...do 


...do 


31 


11 


...do 


...do 


34 


12 


...do 


...do 


35 


13 


...do 


June 6 
June 3 

June 8 
June 9 
June 12 
June 16 
June 17 
...do 
June 25 
June 26 
June 2/ 


32 


14 


May 21 
...do 


30 


15 


34 


16 


...do 


35 


17 


...do.... 


37 


18 


...do 


41 


19 . 


...do 


42 


20 ■-.... 

21 


June 4 

June 7 
...do 


25 

29 


22 


34 


23 


June 8 
...do.... 


34 


24 


June 28 1 July 7 


31 


25 


...do 


...do 


...do 


36 


26 


June 10 
June 11 
...do 


June 25 
June 23 
...do.... 


July 4 
July 1 
July 2 
...do.... 
July 4 


29 


27 


26 


28 


26 


29 

30 


...do 

June 12 
...do.... 
...do 


...do.... 
June 25 


26 
28 


31 

32 IT.. 


...do.... 
...do 


...do.... 
...do 


28 
26 


33 


...do.... 


June 28 
Juno 27 
...do 


July 7 
July 6 
...do.... 


29 


34 


June 13 
...do 


27 


35 


27 


36 

37 


...do 

...do 


...do.... 
...do 


...do.... 
...do.... 


...do.... 
July 11 


27 
28 












Total 


595 


340 


208 


1,143 














Averages for all indi- 


16.08 


9.18 


5.62 


30.89 












1 



LIFE HISTORY AND HABITS : THE PUPA. 87 

These figures show interesting differences from the Michigan 
records. Thus, the average number of days for all larva? in soil before 
pupation is 16.08, as against 12.03 in the Michigan records. The 
average length of the pupal stage at Barnesville, 9.18 days, is notably 
less than shown for Michigan, namely, 14.12 days. However, adding 
together the average larval and pupal stages for each locality shows 
these sums to differ by only 1 day, the lengthening of the larval stage 
in the ground in Georgia being offset by a shorter period in the pupal 
condition. In the Georgia records the average time spent by the 
adults in the ground before emerging is 5.62 days. The average 
time of the 37 individuals spent in the soil is 30.89 days. 

DEPTH OF PUPAL CELL. 

Great diversity of opinion was expressed by the earlier writers as 
to the depth to which curculio larva? entered the soil for pupation, and 
no very accurate observations on this point seem to have been made. 
Riley states that they go below the surface from 4 to 6 inches, and 
remarks that he never found them deeper than 6 inches. Riley and 
Howard, writing in 1S88, state that the larva? seldom burrow to a 
greater depth than 4 or 5 inches. Other writers say "a few inches," 
"2 to 3 inches," "a short distance," and one states "15 to 36 inches." 

Prof. Crandall was perhaps the first to secure exact data on this 
point. In 1903 observations were made on the depth of pupa? in 
ground, including 78 individuals secured under natural conditions 
under trees in orchards, 79 from bottomless soil boxes, and 22 from 
breeding cages in the laboratory — -a total of 179. In 1904 data were 
obtained on 645 individuals, 24 by digging earth under trees, 298 from 
soil boxes, and the remaining 323 from iarva? pupating in the labora- 
tory. Using the records for both seasons obtained under out-of-doors 
conditions — that is, under trees or in soil boxes, sod and cultivated — 
we find that of the total 482, 336, or 69.70 per cent, pupated within 
1 inch of the surface, and 475, or 98.54 per cent, within 2 inches of 
the top of the soil. 

Prof. Crandall's laboratory records do not show important differ- 
ences from those obtained out-of-doors. Some individuals pupated 
at a greater depth, as 8 at 3 inches, 1 at 3| inches, and 2 at 3^- inches, 
as against 1 at 2\ inches, 3 at 2 \ inches, and 3 at 2| inches, under 
out-of-doors conditions, due perhaps to a greater dryness of the soil 
in the laboratory. 

Messrs. Girault and Rosenfeld, in Georgia, in 1906, obtained 
records on the depth of pupation of 121 larva? under natural out-of- 
doors conditions, the soil being a sandy loam. One hundred, or 
82.64 per cent, pupated within 1 inch of the surface, and all, or 100 
per cent, within 2 inches. Other records on depth of pupation in the 



88 THE PLUM CURCULIO. 

same soil in the laboratory do not differ essentially, though 5 larvae 
went to a depth of 2 J inches, one to 2\ inches, and two to 3 inches. The 
above figures are better shown in Table XLIV, which includes also 
records on 40 larvae at the insectary in Washington, obtained by use 
of a soil box, under natural conditions, the soil being a sandy garden 
loam. 

Table XLIV. — Showing depth to which larvse of the plum curculio enter soil for pupation, 

various localities. 













m 


m 








a 






a> 


a> 














A 


A 


,d 




A 


A 


,d 




,d 


A 




Localities. 


o 


A 






13 


o 

Pi 


o 

Pi 


rPl 


a 
Pi 




o 


o 


o 
PI 


o 
PI 


C3 




el 


Pi 


Pi 


n 








PI 












































r*l 


fH 




HW 


r*q 


"'•* 


■"■' 


1-1 


1-1 


^ 


CO 


IN 


CO 


CO 


CO 


m 


m 


Illinois: 
































1903 




45 
137 
61 


55 

100 

34 


40 
91 
21 


19 
50 
23 


16 

77 
11 


3 
39 

17 


1 

51 
10 














179 


1904 


48 


14 

5 


15 
1 


12 


8 

2 


1 


2 


645 


Georgia: 1906 . , . 
District of Co- 


219 
































lumbia: 1905.... 


1 
83 


3 


7 


7 


10 


6 


2 




1 


1 




2 






40 








Total 


246 


196 


159 


102 


110 


61 


62 


20 


17 


12 


12 


1 


2 


1,083 


Percentages 


7.66 


22. 72 


18.10 


14.68 


9.42 


10.16 


5.63 


5.73 


1.85 


1.56 


1.11 


1.11 


0.09 


0.18 


100 



Of the total of 1,083 larvae, 684, or 63.16 per cent, pupated within 
1 inch of the surface, and 1,019, or 94.09 per cent, within 2 inches of 
the surface. These figures show that the great majority of larvae 
pupate comparatively close to the surface of the soil — within a dis- 
tance of 2 inches — a fact to be remembered as bearing on the possi- 
bility of destroying the pupae by timely and proper cultivations, as will 
be later discussed (p. 176). 

SOIL CONDITIONS AFFECTING TRANSFORMATIONS OF THE CURCULIO 

IN THE GROUND. 

Probably no one natural factor, aside from abundance of food, 
exerts a greater influence upon the welfare of the curculio than the 
condition of the soil during its occupancy by the insect, especially 
the degree of moisture. It is a matter of common observation that 
the beetles may long be retarded in their appearance from the ground 
by drought and that after a soaking rain they will come out literally 
in swarms. The necessity for adequate soil moisture for their suc- 
cessful underground transformations and their emergence is doubt- 
less the most important single influence which has prevented their 
spread into the arid regions to the west. As shown under the head- 
ing of geographic distribution, the species has not extended its range 
much west of the one hundredth meridian, which marks, in a general 
way, the beginning of the arid region. 

Some experiments have been made at different times, but espe- 
cially durmg 1910, to secure data on the influence, on the transforma- 
tions of the insect, of different kinds of soil and of normally moist as 
compared with dry soil. 



LIFE HISTORY AND HABITS : THE PUPA. 



89 



In Table XLV are shown results from three root cages. In the 
first the soil was kept normally moist; the second one was moist at 
the beginning of the experiment but was allowed to dry out ; in the 
third cage the soil was dry at the start. June 4, 20 larvae were added 
to cage I, 20 to cage II, and 12 to cage III. 

Table XLV. — Effect of moisture on transformations of the plum curculio in the ground, 

Barnesville, Ga., 1910. 



No. of 
larvse. 


Treatment. 


Date' 
larvae 
entered 

soil. 


Date of 
pupation. 


Life of 
larvae 
in soil. 


Date of 
transfor- 
mation. 


Pupal 

stage. 


Adult 
left soil. 


Life as 
adult 
in soil. 


Total 
life in 
soil. 


1 

2 

3 


Soil kept normally 
moist. 

Total 


June 4 

...do.... 

do 


June 14 

...do 

.do 


Days. 
10 
10 
10 
10 
11 
11 
11 
12 
14 
14 
15 
16 
29 


June 23 
June 22 
June 23 
...do 
...do 
June 22 
June 23 
June 24 
June 26 

...do 

June 27 
June 2S 
July 11 


Days. 
9 
8 
9 
9 
S 
7 
8 
8 
8 
8 
8 
8 
8 


July 3 
...do 


Days. 
10 
11 


Days. 
29 
29 


4 

5 


...do.... 
...do.... 
...do 
...do.... 
...do.... 
...do.... 
...do.... 
...do.... 
...do.... 
....do.... 


...do 
June 15 

...do 

...do 

June 16 
June IS 

...do 

June 19 
June 20 
July 3 


July 3 
June 30 


10 

7 


29 
26 


7 

8 

9 

10 

11 


June 29 
July 1 
...do 

July 4 


6 

7 
5 
8 


25 
27 
27 
30 


12 


July 7 


9 


33 










13 


173 
13.30 


106 
8.15 


73 

8.11 


255 














28.33 




At start soil nor- 
mally moist but 
allowed to dry 
out. 

Total 


June 4 
do 


June 13 
.do .. 


June 22 

...do 

...do 

June 23 
June 22 
June 23 

...do 

...do 
June 24 
June 27 




1 


9 
9 
9 
10 
10 
10 
10 
11 
11 
12 


9 
9 
9 
9 
8 
9 
9 
8 
9 
11 






2 








3 

4 


...do ... 
...do.... 
...do 

1 do 


...do 

June 14 

...do 

do 


July 4 


12 


30 


5 








6 








7 


do 


do 








8 


...do.... 
...do 

[...do.... 


June 15 

...do 

June 16 








9 








10 
















10 


101 
10.1 


90 
9.0 


12 
12 


30 














30 




VSoil entirely dry. . 
Total 


/June 4 
\...do 


June 14 
...do 


June 23 
...do 






1 


10 

10 


9 
9 






2 
















2 


20 
10 


18 
9 





































As will be seen, 13 larvae in cage I entered the soil and reached the 
pupal stage; only 9 adults, however, emerged. In cage II, 10 larvae 
passed the pupal stage, but only one adult succeeded in emerging. 
In the third cage most of the larvae were unable to work themselves 
below the soil to any extent on account of dryness of earth, and by 
June 13 several were found dead, evidently drying up. Only two 
individuals reached the pupal stage, and no adults emerged. 

A series of observations was started on larvae placed in soil in jelly 
glasses, as detailed in Table XL VI. 



90 



THE PLUM CUECULIO. 



Table XLVI. — Effect of moisture on transformations of the plum curculio in the ground, 

Barnesville, Ga., 1910. 



SOIL KEPT NORMALLY MOIST. 



Jar No. 


Larvae. 


Beetles 
emerging. 


Average 
time in soil. 


Per cent 
emerging 
as adults. 


I 


16 
13 

11 
17 
8 
15 
12 
14 


15 
12 
11 
13 
8 
12 
11 
14 


Days. 
25.53 
25.50 
25.27 
26.15 
28.12 
25.91 
24.00 
23.35 


93.7 


II 


92.3 


V 


100.0 


VI 


76.5 


VIII 


100.0 


XI 


80.0 


XIII 


91.7 


XVII 


100.0 






Total 


106 


96 










90.56 













SOIL AT FIRST MOIST, BUT ALLOWED TO DRY OUT. 



XII i 


15 
12 
14 
12 
5 


2 
3 
2 
8 
3 


27.50 
25.66 
28.00 
26.37 
26.66 


13.3 


XIV 


25.0 


XV 2 


14.3 


XVI 


66.6 


XVIII 


60.0 






Total 


58 


18 










31.03 













SOIL DRY. 



Ill 


13 
10 
17 
9 
12 


None. 
None. 
None. 
None. 
None. 






IV - 






VII 






IX 






x 








Total 








61 































i Soil watered 34 days after entering of soil by larvse, 9 more beetles promptly appearing. 
2 Soil watered 36 days after entering of soil by larvae, one beetle appearing the following day. 

In the series of jars with normally moist soil, a total of 106 larvae 
was used, yielding 96 adults, or 90.56 per cent. In jars where the 
soil was allowed to dry out, and without further watering, a notice- 
able decrease in the number of adults emerging is shown. From a 
total of 58 larvae only 18 adults, or 31.03 per cent, developed. Where 
dry soil was used no adults whatever developed from the 61 larvae 
used. 

Four wooden boxes, 10 by 12 by 8 inches, were used in a more 
extensive test. In two of the boxes ordinary Georgia red clay was 
used, one being kept moist, while the other was dry but was subse- 
quently watered as stated in the footnote. In the other two boxes 
a sandy loam was used, one being kept moist and the other dry. 
The soil in all boxes, however, was moist at the time the larvae were 
put in, to enable them better to establish themselves. The boxes 
were covered with wire screen and kept out of doors protected from 
the sun. (For detail, see Table XL VII.) 



LIFE HISTORY AND HABITS: THE PUPA. 



91 



Table XLVII. — Effect of moisture on transformations of the -plum curculio in the ground, 

Barnesville, Ga., 1910. 



Dates of emergence of 
adults and parasites. 


Red clay kept nor- 
mally moist (247 
larvae, Aug. 6-9). 


Red clay moist at 
start but allowed 
to dry out (245 
larvae, Aug. 6-9). 


Sandy loam kept 
normally moist 
(280 larvae, Aug. 
10-13). 


Sandy loam moist at 
start but allowed 
to dry out (288 
larvae, Aug. 10- 
13). 




Adults. 


Para- 
sites. 


Adults. 


Para- 
sites. 


Adults. 


Para- 
sites. 


Adults. 


Para- 
sites. 


Aug 29 




2 
3 
6 
4 
4 
5 
3 
1 
1 
1 




1 










30 














31 
















Sept. 1 


1 
2 
2 

19 

15 

17 

17 

12 

15 

12 

6 

6 

7 

7 

6 








1 
5 

4 
3 

7 
7 
2 




1 


2 










3 


3 






2 

2 

8 

16 

28 

12 

18 

14 

5 

7 

13 

11 

4 

3 

3 

3 

1 

4 

2 

2 




2 


4 








3 


5 








1 


6 








3 


7 


167 
8 
1 
1 


1 






8 


1 




9 




1 




10 




2 
2 




11 .. 




1 




12 










13 .. 














14 .. 










1 




15 








1 




16 












17 . 


5 
2 
5 
1 
1 














18 . 




1 










19 .. 










20 . 














21 .. 














22 .. . . 














23 


1 














24 .... 








5 








25 . 


2 














26... 
















27 


















28 


















29 


1 
1 








1 








30 






























Total 


163 
65 99 


30 


78 
31 84 


2 


164 
58.57 


32 


6 
2.08 


13 


Percentage 

Percentage adults 
and parasites emerg- 




7S 13 


32 a*; 


70 


00 


6. 


90 













1 The soil in box had dried so hard that it was considered impossible for any beetles to emerge. To deter- 
mine the effect of wetting, water was applied on the evening of Sept. 6. The record shows the prompt 
emergence of the beetles. 

In the case of the red-clay soil kept normally moist, 65.99 per cent 
of the larvse transformed to adults, or if account be taken of the para- 
sites, 78.13 per cent. From the box containing dry red clay soil it is 
highly probable that not a single adult would have been able to escape 
without the thorough soaking given on September 6. That many 
beetles were still alive is shown by the prompt emergence of 67 the 
day following, and 11 more during, the next 3 days. The effect of 
drought on this type of soil is also shown to reduce emergence of para- 
sites. A total of 32.65 per cent of the individuals in this box are 
accounted for as beetles or parasites. 

From the normally moist sandy -loam soil 164 beetles developed and 
32 parasites, giving a total percentage of individuals accounted for 
of 70 per cent as compared with the emergence record of 6.90 per cent 
of the dry sandy loam soil. 



92 



THE PLUM CUECULIO. 



From all of the foregoing data it is clearly shown how important is 
moisture for the transformation of the curculio in the soil. In general, 
no adults issued from a dry soil, and in a soil moist at time of entrance 
of larvae, but allowed naturally to dry out, the number emerging was 
greatly rsduced, from 88.23 per cent to 27.94 per cent, as compared 
with condition of checks. Dryness does not appear to affect the 
length of the stages, as the average days spent in the soil of individuals 
of both series is about the same. As shown in Table XLV the mor- 
tality seems to be largely after transformation to the beetle stage has 
occurred, if the soil was moist at the time the larvae entered. 

THE ADULT. 

PERIOD OF EMERGENCE OF BEETLES. 

As elsewhere shown (p. 48) oviposition extends over several weeks, 
or even months. It follows that the beetles resulting from the eggs 
will emerge during a similar interval of time, and this period may be 
considerably modified by the condition of the soil, as whether dry, or 
sufficiently moist to permit the prompt escape of the beetle when suf- 
ficiently hardened. 

Records of the emergence of beetles during the season, as obtained 
from the larval emergence records detailed in Table XXII, are shown 
in Table XLVIII from Barnes ville, Ga.; Siloam Springs, Ark.; Wash- 
ington, D. C; and Douglas, Mich. 

Table XLVIII. — Emergence/win the soil of beetles of the plum curculio during the season, 

several localities. 



Dates of 
emer- 
gence. 


Barnes- 
ville, Ga. 


Siloam 

Springs, 

Ark. 


Washing- 
ton, D.C. 


Doug- 
las, 
Mich. 


Dates of 
emer- 
gence. 


Barnes- 
ville, Ga. 


Siloam 

Springs, 

Ark. 


Washing- 
ton, D.C. 


Doug- 
las, 
Mich. 


June 6 


9 

13 

18 

26 

33 

105 

135 

132 

150 

141 

108 

128 

61 

47 

57 

50 

38 

43 

33 

19 

16 

1 

24 

9 

11 








July 1.... 
2.... 
3.... 
4.... 
5.... 


9 
2 
6 
6 


14 

83 

107 

30 

12 

3 

55 

2 

2 

9 

7 

56 

12 

14 

2 

16 

7 

64 

10 

13 

10 

3 

5 

9 

6 


69 
41 
49 
54 
60 
15 
8 
20 
39 
43 
29 
17 
39 
15 
96 
• 31 
80 
56 
16 
34 
141 
197 
67 
55 
25 




7 










8 










9 










10 










11 


1 

5 

1 

4 

17 

15 

16 

36 

45 

44 

45 

7 

115 

133 

142 

65 

28 

181 

100 

45 






6.... 

7.... 


4 




12 








13 




1 


8.... 
9.... 
10.... 


3 
1 




14 








15 








16 






11 . 






17 






12.... 
13 . 


3 




18 








19 






14.... 






20 






15 .. 






21 






16. . . . 

17 . 


1 




22 








23 






18.... 






24 






19... 






25 


'6 
3 

22 
14 
14 




20 






26 


21 






27 


22 






28 


23 






29 


24 






30.... 


25 






26 






Total 


1,407 


1,045 


62 




27 




4 
1 


44 
32 






28. . . . 







LIFE HISTORY AND HABITS : THE ADULT. 



93 



Table XL VIII. 



-Emergence from the soil of beetles of the plum curculio during the season, 
several localities — Continued. 



Dates of 
emer- 
gence. 


Barnes- 
ville, Ga. 


Siloam 

Springs, 

Ark. 


Washing- 
ton, D.C. 


Doug- 
las, 
Mich. 


Dates of 
emer- 
gence. 


Barnes- 
ville, Ga. 


Siloam 

Springs, 

Ark. 


Washing- 
ton, D.C. 


Doug- 
las, 
Mich. 


July 29... 




1 

2 


15 
7 

7 




Sept. 1.... 
2.... 
3.... 
4.... 
5.... 
0.... 
7.... 
8.... 


16 
3 
5 
3 

16 
3 
5 


2 
1 






30... 








31... 


















Total. 


35 


559 


1,401 


















Aug. 1 






. 12 


2 
2 
3 
6 
3 

11 
6 
5 
6 
6 
6 
3 

10 
G 
4 
6 
3 
4 

1 
4 
2 

1 








2.... 




1 
4 








3.... 




10 
4 
4 
2 
1 
2 


9.... 
10.... 
11.... 


2 
5 








4 










5.... 




1 








6.... 




12.... 


r 








7.... 






13.... 










8.... 




2 


14.... 
15.... 
16.... 


8 
3 








9.... 


2 
2 
2 
5 
2 
3 
1 
2 
3 
4 
6 
11 
3 
5 
29 
5 
21 
16 
13 
3 
13 
24 
19 








10.... 


1 


1 

1 








11.... 


17.... 

is...: 

19.... 
20.... 
21. 


3 
2 
3 
3 








12.... 


6 

35 

10 

5 

6 

31 

22 

12 

14 

9 

13 
6 
5 








13.... 










34.... 










15.... 










16.... 




22 










17.... 


3 


23.... 










18.... 


24. 










19---. 


4 


25.... 










20.... 


26. 










21.... 


3 


27.... 










22.... 


28.... 

Total. 

Total 
for 
sea- 
son. 


2 








23 










24.... 




82 


* 5 






25 










26.... 


3 






1,718 


1,803 


1,510 




27.... 








28.... 


4 








29.... 






102 


30.... 










31.... 


4 
















Total. 


194 


194 


47 


102 





The data do not show the entire range of time over which beetles 
may emerge from a given locality, but they indicate about what hap- 
pens in a particular orchard. Later records could doubtless have 
been gotten had other fruits been used as a source of larvae, after the 
gathering of the peach crop. 

The Barnesville, Ga., record is perhaps the most nearly complete, 
since at that place there is little fruit available for the curculio after 
the harvesting of Elberta peaches. This record shows an interval 
from June 6 to September 28 during which beetles were emerging — 
a period of 114 days (see fig. 21). But from larvae from some late 
seedling peaches beetles continue to emerge up to November 9, 
giving a total period of 156 days. Only the cold weather prevented 
still further emergence, since on November 10 there still remained 
in the soil fully matured adults as well as many pupae and even a 
few larvae. These were from a batch of 107 larvae from seedling 
peaches, the last to be secured. The larvae left the fruit September 
18 to October 15, and 15 beetles emerged October 19 to November 
9. The soil in the box was examined November 10, when there 
were found 6 beetles ready to emerge, 28 live healthy pupae, 5 live 



94 



THE PLUM CURCULIO. 



larvae, and 1 cocoon of Triasjris curculionis, var. rufus. It thus 
appears possible that some few individuals may pass the winter in 
the soil, both in the adult stage and as pupae, and emerge the follow- 
ing spring. 

During 1905-6, at Fort Valley, Ga., adults were reared as early as 
May 22 and as late as October 5, an interval of 136 days. In this 
case the food for the late rearings was Crataegus. 







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Fig. 21. — Diagram showing normal emergence from soil of beetles of the plum curculio for the season 
at Barnesville, Ga. (Original.) 

At Siloam Springs, Ark., the interval of emergence, June 11 to 
September 3, includes 84 days. Later miscellaneous records of 
emerging adults reared from apples, however, were, up to October 
23, giving a total emergence interval of 134 clays (see fig. 22). 





6 /G 26 6 /6 26 S /S 2S * /4 24. 


to 400 

! 

%200 
1 

S/oo 

1 

Q 


417 


























V 7 ' 














































\/64 
























Uo 




68 


-Z^'J-. 


loo 


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O i i 


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22 


ZL£_t_ 


o oLo 



Fig. 22. 



-Diagram showing normal emergence from soil of beetles of the plum curculio for the season 
at Siloam Springs, Ark. (Original.) 



The Washington, D. C, records show an interval from June 25 to 
August 21, 57 days. Other miscellaneous records for that locality 
give adults as early as June 15 and as late as August 30, or 76 days. 
Unquestionably adults are emerging even later. 



LIFE HISTORY AND HABITS : THE ADULT. 95 

The Douglas, Mich., records, as pointed out for the larval emer- 
gence data, are manifestly incomplete, especially as regards the latter 
part of the season. They do, however, show the emergence of 
beetles from all larva? from peaches regularly collected throughout 
the season, as previously shown. The interval here is only 23 days, 
from August 1 to 23. 

Incomplete records from Youngstown, N. Y., give for the earliest 
beetles July 18 and the latest October 6, a period of 80 days. 

At North East, Pa., the first emergence was noted July 15, and 
beetles were reared in confinement up to August 21, and unques- 
tionably appeared much later. The period observed, however, is 
37 days. 

In Illinois, as stated by Prof. Crandall, earliest beetles were reared 
July 17, and continued to emerge until November 7, a period of 113 
days. His observations were made on apple, on which fruit the 
insect would have opportunity for late egg laying, which would not 
be true in the case of peaches and plums in the South. Unquestion- 
ably the Illinois records more nearly show the period of emergence 
for the Northern States where suitable fruit is not at any time 
wanting. The above data are shown below in tabular form. 

Period of emergence of beetles. ' 

Days. 

Georgia — May 22 to Nov. 9 171 

Arkansas — June 11 to Oct. 23 '. v 134 

District of Columbia — June 15 to Aug. 30 76 

Michigan — Aug. 1 to Aug. 23 23 

New York— July 18 to Oct, 6 80 

Illinois — July 17 to Nov. 7 113 

PKOPORTKW OF SEXES. 

The proportion of males and females was determined at different 
times, with overwintering and newly emerged adults. 

In a lot of 80 beetles reared in confinement at Washington during 
June, 1905, 30 were males and 50 females. In another lot reared as 
above, 21 were males and 45 females. Of 140 adults jarred from 
trees in May, 1905, at Arundel, Md., and hence overwintering beetles, 
70 were males and 70 females. 

At Myrtle, Ga., in 1906, of 200 beetles jarred from trees May 14 to 
21, 83 were males and 117 females, and of those taken May 22 to 30, 
73 were males and 107 females, a total of 180. One hundred beetles 
reared from various fruits during May and June gave 51 males and 
49 females. In a lot of 175 beetles reared from May 28 to August 
12, 81 were males and 93 females. In a lot of 840 beetles jarred 
from peach at Fort Valley, Ga v in 1905 7 339 were males and 501 
females. 



96 THE PLUM CURCULIO. 

Considering the proportion of sexes of those reared, there are found, 
of the total 681, 306 males and 375 females, a percentage of females 
of 55. 

Of those jarred from the trees and which had thus passed the winter, 
there is a. total of 1,180, of which 688 are females and 492 males, a 
percentage of females of 58.3, showing a slight increase in mortality 
during winter of males over females. 

CHOICE OF FOOD BY CURCULIO. 

Practically all writers agree that plums are the preferred food of 
the curculio. Under orchard conditions, where several fruits are 
present, as apple, plum, peach, etc., taking the season as a whole, 
the plum is perhaps somewhat more injured than the others. Varie- 
ties of plums, especially Japanese sorts, are early to develop fruit, 
and consequently are first attacked by the beetles, and on these 
they seem for a while to concentrate. With the development of 
peaches, apples, and pears, these are also attacked for feeding and 
egg-laying purposes. In general, however, it is undoubtedly true 
that plums are the favorite food of the curculio, and are also pre- 
ferred for oviposition places. 

Attempts have been made to obtain data on the fruits preferred 
by the insect by supplying beetles with various fruits at the same 
time. 

Tests were made. by Mr. Girault, May 17, 1905, in which 5 fruits 
each of plum, peach, quince, and pear were placed in jars and each 
supplied with 10 curculios. Upon examination, May 20, 72 hours 
later, results were as follows: On plum, the egg and feeding punc- 
tures were so abundant as practically to cover the whole surface of 
the fruit; on peach there were numerous punctures, but they were 
less abundant than on plum; on pear there were no punctures on 
fruit, but a few were on the fruit stems ; on quince no punctures were 
seen on fruit, but a few were on fruit stems. Expressed in percent- 
ages of injury, plum would be 100, peach 50, pear 10, and quince 10. 

Mr. J. H. Beattie placed 100 beetles in a jar containing foliage of 
peach, plum, pear, and quince. Two d&js later peach leaves had 
been riddled by feeding; plum leaves were moderately eaten; the 
quince showed a few feeding marks, while the pear foliage had not 
been touched. 

June 7, 1906, 12 beetles were confined with two large Elberta 
peaches and five wild plums. After 12 hours, punctures were noted 
as follows: On plum, egg punctures 37, feeding punctures 30; on 
peach, no feeding or egg punctures found. 

April 23, 1906, 15 curculios were confined under a jar with three 
fruits each of apple, peach, wild plum, pear, and cherry. The results 



LIFE HISTORY AND HABITS I THE ADULT. 



97 



gave a preference of fruit, as shown by feeding and egg punctures, 
in the following order: Apple, peach, plum, cherry, and pear. 
Further data are given in Table XLIX. 

Table XLIX. — Attractiveness of different fruits to the plum curculio. 



Lot I. 


Lot II. 


Lot III. 


Lot IV. 


Dates. 


Punctures. 


Dates. . 


Punctures. 


Dates. 


Punctures. 


Dates. 


Punctures. 




















Apple. 


Peach. 




Apple. 


Peach. 




Apple. 


Plum. 




Apple. 


Plum. 


May 1 


5 


5 


May 13.. 


"10 


10 


May 20. . 


5 


5 


May 28. . 


5 


5 


2 


9 


11 


14.. 


10 


11 


21.. 


9 


11 


29.. 


10 


10 


3.... 


13 


7 


15.. 


8 


12 


22.. 


12 


8 


30.. 


10 


10 


4.... 


13 


7 


16.. 


11 


9 


23.. 


12 


8 


31.. 


5 


15 


5.... 


14 


6 


17.. 


11 


9 


24.. 


12 


8 


June 1... 


8 


12 


6.... 


13 


7 


18.. 


11 


7 


25.. 


10 


10 


2... 


13 


7 


7.... 


17 


3 


19.. 


10 


10 


26.. 


8 


14 


3... 


11 


9 


8.... 


10 




Total. 






27.. 
Total. 


7 


3 


4... 
Total. 


5 


5 


Total. 


94 


46 


71 


68 


75 


67 


67 


73 



A total of 165 punctures is shown for apple, as against 114 on peach, 
and a total for apple of 142 against 140 on plum. 

The preference of the curculio for smooth fruit is shown by an 
experiment by Mr. Girault in 1906. In a jar were placed 20 beetles, 
8 males and 12 females, which were supplied on several successive 
days for four-hour periods, with 3 normal peaches and 3 peaches 
from which the fuzz, or pubescence, had been removed. The results 
are as follows: 

Table L.— Showing preference of plum curculio for smooth versus fuzzy peaches, Myrtle, 

Ga., 1906. 





Fruit 
No. 


Normal, with pubescence. 


Pubescence removed. 


Dates. 


Egg 
punc- 
tures. 


Egg 
punctures 
with eggs. 


Feeding 
punc- 
tures. 


Egg 
punc- 
tures. 


Egg 
punctures 

with eggs. 


Feeding 
punc- 
tures. 


Apr. 20 


1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 






2 
2 

4 


16 
15 
11 
1 
11 
13 
11 
13 
8 
4 
9 
4 


13 

9 

7 

1 

10 

12 

10 

11 

8 

3 

9 

4 


2 


20 


1 


1 


4 


20. 


3 


21 






5 


21 








2 


21 






1 

1 
2 
1 
3 
1 
3 


6 


22 






9 


22 






7 


22 






5 


23 


2 


1 


5 


23. 


5 


23 






3 










Total.... 




3 


2 


20 


116 


97 


56 









A total of 3 egg and 20 feeding punctures is shown on the normal 
fuzzy fruit as compared with 116 egg punctures and 56 feeding 
punctures on fruit from which the hairs had been removed. 

17262°— Bull. 103—12 7 



98 THE PLUM CURCULIO. 

EXTENT OF FEEDING OF THE RESPECTIVE SEXES. 

The extent to which feeding is done by the respective sexes of the 
curculio during their lives is shown in Table LI. Individuals of 
each sex were separately confined and each beetle supplied daily 
with 4 wild plums, examinations of the fruit being made daily. 

Table LI. — Extent of feeding of each sex of the plum curculio during the season, Myrtle, 

Ga., 1906. 





Feeding punctures by males. 


Feeding punctures by 
females. 


Dates. 


Bee- 
tle 
No. 1. 


Bee- 
tle 
No. 2. 


Bee- 
tle 
No. 3. 


Bee- 
tle 
No. 4. 


Bee- 
tle 
No. 5. 


Bee- 
tle 
No. 6. 


Bee- 
tle 

No. 7. 


Bee- 
tle 
No. 8. 


Bee- 
tle 
No. 1. 


Bee- 
tle 
No. 2. 


Bee- 
tle 
No. 3. 


Bee- 
tle 
No. 4. 


Apr. 16 • 


3 
3 
2 
3 

2 
8 
1 
2 
1 
4 
4. 
5 
2 
1 


4 
4 
4 
2 
1 
7 
2 
1 
1 
4 
5 
1 
,2 
2 
1 
3 
5 
2 
. 3 
3 
1 
5 
1 
3 
1 
1 
4 
3 
4 
7 
2 
2 
3 
2 
2 
3 
1 
1 
1 
4 
3 
4 
7 
5 
2 
1 
4 
8 
6 
5 
3 
2 
4 

1 


3 

2 
2 

6 
3 

2 

2 
11 
4 
5 
5 
3 
4 
6 
10 
5 
1 
5 
2 
3 
2 
2 
1 
1 
1 
2 
1 
4 
3 
5 
3 
4 
1 
3 
2 


4 
2 
2 
3 
2 
6 
5 
1 
3 
3 
4 
3 
2 
4 
2 
5 
3 

0) 


1 
1 
2 
1 
1 
1 
1 
1 
1 
1 
3 
2 
3 
1 
2 

1 


1 
1 


2 
1 


3 
2 
2 
2 

1 
1 

2 

1 
1 
1 

1 
3 

1 
2 
1 

1 
2 
2 


13 
3 
5 
8 
1 
2 
8 
2 
1 
5 
4 
5 
3 

12 
2 
1 
7 
8 
3 
2 
2 
3 
4 
8 
1 
5 
6 
5 
6 
6 
4 
4 
6 
9 
4 
4 
5 

6 
4 
6 

7 
5 
4 
7 
5 
2 
2 
5 
4 
4 
5 
3 
5 
4 
4 

1 

4 


12 
5 
4 
2 
4 
5 
2 
2 
5 

4 
3 
5 
4 
3 
2 
6 
8 
5 

8 
4 
5 
5 
5 
5 
5 
6 
7 
4 
4 
8 
4 
4 
12 
6 
6 
7 
4 
5 

12 
14 
7 
6 
8 
2 
1 
4 
4 
6 
3 
1 
1 
1 
3 
4 
4 
8 
8 


8 
4 
5 
5 
3 
3 
3 
3 
4 
4 
5 
8 
8 
3 
8 
2 
8 

19 
9 
2 
3 
1 
8 
6 
1 
2 
2 
3 

10 
3 
4 
5 
8 
4 

13 

10 
5 
2 

11 
9 
2 
6 
3 
3 
1 
1 

2 
3 
4 
2 
3 
2 
7 


7 


17 


4 


18 


5 


19 


3 


20 


1 
2 
1 
1 
1 

2 
2 
1 
1 
1 
1 
1 
1 
1 
1 

1 
2 
1 
1 
1 
2 
1 
1 


2 
1 
3 
3 
2 
1 
1 
1 
2 
2 
1 
4 
1 
3 
3 

2 
2 
3 
2 


6 


21 


13 


22 


8 


23 


3 


24 


1 


25 


6 


26 


4 


27 


11 


28 


3 


29 


8 


30 


4 




2 
4 
1 
3 
2 
2 
2 
1 
3 
2 
3 
1 
1 
3 
7 
3 
3 
5 
2 
2 
1 
5 
2 
1 
1 
4 
3 
1 
5 
1 
5 
4 
1 
1 
1 
4 
4 
5 
3 
2 
6 


5 


2 


3 


3 


11 


4 


1 


5 


3 


6 




1 

7 
2 


3 


7 


1 


8 




9 


3 


10 




3 
2 
1 
1 
1 
1 
4 
5 
6 
4 
1 
2 
5 
5 


2 


11 


1 

2 


3 
2 


2 


12 


2 


13 


3 


14 


2 


1 

2 

7 
2 

5 
1 

2 
1 


3 


15 


1 


16 


1 

1 

4 


2 
1 
3 

2 


7 


17 ; . . 


4 


18 


1 


19 


6 


20 


14 


21 


1 
2 

3 
1 

1 
1 

2 
6 
3 
3 
4 
1 
1 
3 
2 


2 
2 
1 


3 


22 


2 


23 


2 


24 


2 


25 


2 
4 
8 
1 
5 
5 
7 
6 
2 
10 
3 




1 

2 
5 
3 
1 
1 
1 
5 
2 
4 
5 


7 


26 


2 
3 
1 
2 
3 
2 
4 
1 
2 
1 
3 
2 


2 
3 
2 
2 
1 

7 
3 

3 
3 

2 
3 

( 2 ) 


6 


27 


13 


28 


3 


29 


2 


30 


4 


31 


3 




2 


2 


2 


3 


2 


4 


8 


5 


3 


6 


6 
2 
6 
2 
4 






4 


7 






7 


8 




6 


1 

2 
1 

2 


i 

5 
1 
1 


4 


9 


2 


10 




4 
2 


3 


11 


16 












14 










■;::i . 








13 



» Died. 



Escaped. 



LIFE HISTOEY AND HABITS: THE ADULT. 



99 



Table LI. — Extent of feeding of each sex of the plum curculio during the season, Myrtle, 

Ga., 1906— Continued. 





Feeding punctures by males. 


Feeding punctures by 
females. 


Dates. 


Bee- 
tle 
No. 1. 


Bee- 
tle 
No. 2. 


Bee- 
tle 
No. 3. 


Bee- 
tle 
No. 4. 


Bee- Bee- 
tle tie 

No. 5. No. 6. 


Bee- 
tle 
No. 7. 


Bee- 
tle 
No. 8. 


Bee- 
tle 
No. 1. 


Bee- 
tle 
No. 2. 


Bee- 
tle 
No. 3. 


Bee- 
tle 

No. 4. 


June 14 
















22 

22 

7 

8 

2 

19 

15 

3 

3 

8 

5 

3 

1 

3 


2 
7 
8 
4 
7 
10 
4 
8 
5 
2 
2 


1 
1 

2 

2 

1 
1 
4 
2 


8 


15 










| 






6 


16 










1 






5 


17 










1 






3 


18... 


4 


3 


1 




6 | 3 


8 




4 


19 


5 


20 










i 






9 


21 










i 






9 


22 




3 


5 




1 


1 






5 


23 








8 


24 
















10 


25. . . 


















3 


26. 


















2 

2 

( 2 ) 






27 


















5 

( 2 ) 


2 


28 


C 1 ) 


















29 




















30 


























July 1 




6 


7 




1 


1 














3 




0) 




4 
3 


6 


1 

5 


4 


6 












C 1 ) 




7 




4 


5 




3 








9 










3 
1 








12 
























17 


















( l ) 






18 










0) 














19 




















G) 




20 






( l ) 


















30 




8 




















31 
















C 1 ) 








Aug. 4 






















C 1 ) 


7 




(') 














































Total 


157 


186 


210 


54 


127 


81 


102 


86 


404 


361 


288 


369 







1 Died. 



2 No record. 



The individual records show that the females feed more actively 
than the males. Most of the males had practically ceased feeding 
by June 11, although the females continued to feed freely during the 
rest of the month. The average number of feeding punctures per 
male, excluding No. 4, is 135.55, as compared with the average of 
355.50 for each female. 



OPERATION OF EGG LAYING. 

The process of egg laying of the plum curculio has excited the 
interest of many observers, and it has been frequently described. 
There is much variation in the statements as to time occupied, se- 
quence, and relative time of the various acts, etc. Many writers 
have not distinguished at all the separate steps involved, as, for 
example : 

As soon as the plums, peaches, cherries, and apples are set the curculio commences 
operations, imprinting the familiar crescent and placing an egg inside. 



100 THE PLUM CURCULIO. 

Riley's account of oviposition is, however, much more complete, 
as follows: 

That the egg is deposited in the following manner, the whole process requiring 
about five minutes: Having taken a strong hold on the fruit, the female makes a 
minute cut with the jaws, which are at the end of her snout, just through the skin of 
the fruit, and then runs the snout under the skin to the depth of one-sixteenth of 
an inch, and moves it back and forth until the cavity is large enough to receive the 
egg it is to retain. She next changes her position, and drops an egg into the mouth 
of the cut; then, veering round again, she pushes it by means of her snout to the end 
of the passage, and afterwards cuts the crescent in front of the hole so as to undermine 
the egg and leave it in a sort of flap, her object apparently being to deaden this flap 
so as to prevent the growing skin from crushing the egg, though Dr. Hull informs me 
that he has repeatedly removed the insect as soon as the egg was deposited and before 
the flap was made, and the egg hatched and the young penetrated the fruit in every 
instance. 

Prof. J. M. Stedman also described the process: 

In making punctures for the purpose of depositing eggs, the females also eat the 
tissues of the apple, and this is probably the reason why during the egg-laying season 
they do not make as many purely feeding punctures as they do earlier and later in 
the season. The female first eats a small hole through the skin and then eats the pulp 
back about one-sixteenth of an inch, thus making a small cylindrical hole, usually 
quite parallel to the skin. She then turns around and deposits an egg in this hole, 
which is just large enough to receive the egg nicely. Having accomplished this, she 
then eats the tissue while cutting a small crescent-shaped hole through the skin and 
into the pulp so as to partly surround and partly undermine the egg. 

In Prof. Crandall's studies many attempts were made to secure 
data on the entire operation, but owing to the difficulties of so doing, 
three instances only from start to finish were observed, as follows: 

In the first observation, the female moved about the apple for several seconds, keeping 
the end of her beak in contact with the surface, as if seeking a favorable spot. When 
the exact spot was decided upon, the minute jaws at the end of the snout began a 
rapid movement which quickly made an opening through the skin. This opening 
was no larger than necessary for admission of the tip of the beak. No skin was re- 
moved; it was simply torn and thrust aside to give access to the pulp below. Later, 
as the excavation proceeded, the broken skin was seen as a sort of fringe around the 
beak at the surface of the fruit. As soon as excavation in the pulp was commenced, 
the beak was deflected backward so that the work was carried on under the insect,, 
just beneath the skin and nearly parallel with the surface. As the work advanced, 
the opening through the skin became slightly enlarged by lateral motions of the beak. 
The pulp was all eaten as excavated. During the process the beak was not once 
withdrawn, nor was there any cessation of motion. When the excavation of the 
cavity was completed the beak was withdrawn by a quick motion, the insect turned 
about, adjusted the tip of the abdomen to the opening and deposited an egg, which 
was forced to the extremity of the excavation by the ovipositor. The insect now 
rested without motion for two minutes; then, turning again, proceeded to cut the 
crescent in front of the egg. This crescent puncture was not wholly a separate punc- 
ture, but, starting in the original opening through the skin, was cut laterally in either 
direction, partly by the jaws and partly by crowding the beak first one way and then 
the other. The direction of the beak was but little deflected from the perpendicular 
and the cut was made as deep as the length of the beak would allow. The pulp torn 



LIFE HISTOEY AND HABITS: THE ADULT. 101 

away in making the crescent was eaten, just as was done in excavating the egg cavity. 

The crescent completed, the insect walked away, drew the legs closely under the 

body, and settled down, apparently to sleep. The time occupied in the process 

described was distributed as follows: 

Minutes. 

Excavating egg cavity i 9 

Deposition of egg 1 

Rest 2 

Cutting the crescent 3£ 

Total - 15^ 

The egg cavity was cylindrical, with a rounded bottom, and by measurement was 
found to be 0.04 inch in depth. The egg when deposited very nearly filled the 
cavity. 

The second observation of the complete process was nearly identical with the one 
described. The insect spent no time in choosing the exact spot, but went to work 
at once. It worked in a more leisurely way and did not excavate as deep an egg 
cavity. Eleven minutes were spent on the cavity, 2 minutes in depositing the egg, 2 
minutes in rest, and 4 minutes in cutting the crescent, a total of 19 minutes. The 
egg cavity measured 0.035 inch in depth and was completely filled by the egg. On 
completion of the process the insect moved a short distance and immediately began 
a second cavity. 

Essential differences from procedure in the two preceding cases were noted in the 
third complete observation. Excavation of the egg cavity was the same, except that 
it was deeper in the pulp and of greater depth. After depositing the egg the beetle 
turned and with her beak worked the egg back to the bottom of the cavity. Then 
she began tearing off bits of skin and pulp, which were carefully packed in, above the 
egg, until the cavity was full. Following this, the crescent was cut in much the same 
manner as in the preceding cases. Then she appeared to make a final inspection, 
and added some further packing above the egg. Finally the work appeared to be 
satisfactory and she walked away and began a second puncture. The time consumed 
in this process was longer than in the others, and was divided as follows: 

Minutes. 

Excavating egg cavity 12 

Depositing egg \\ 

Placing the egg with the beak 2 

Packing the cavity 4 

Cutting the crescent 4 

Finishing touches 3 

Total 26 \ 

Mr. Johnson observed the operation of egg laying in 1905 at 
Youngstown, N. Y., in a Niagara plum, from which the calyx had 
recently fallen. The excavating of egg cavity, placing of egg, packing 
of cavity, and cutting the crescent was done without a pause and 
occupied 10 minutes. 

According to the observations of Mr. J. H. Beattie at Fort Valley, 
Ga., in 1905, a beetle was occupied 1 minute in making the egg 
cavity hi a plum, after which, turning around, it deposited an egg 
in about 5 seconds, a few seconds more being required in pushing 
the egg into the cavity. However, in cutting the crescent 6 minutes 
were occupied, a total of a little more than 7 minutes. 



102 THE PLUM CUECULIO. 

Mr. Girault observed a beetle at Myrtle, Ga., May 7, throughout the 
entire operation. This individual had been previously starved and 
was furnished with a fresh wild plum upon which it climbed at 
4.36 p. m., settling on the side. It carefully examined the surface of 
the fruit before beginning oviposition, as follows: 

Minutes. 
Egg cavity begun 4.43. 

Egg cavity finished 4.51 8 

Egg deposited 4.51-lf I 

Egg pushed in cavity 4.51f-2J £ 

Packing egg cavity 4.52J-4J 2\ 

Began crescent 4.55 

Crescent finished 5.08 < 13 

Total 24J 

During the process the body was in an extended position, legs well 
out grasping the fruit, and while excavating the cavity the body was 
at an angle of about 45°. Difficulty was evidenced in holding to the 
fruit. The tarsi were continually being lifted and extended, and 
applied to the fruit, and this was followed by a drawing motion, to 
engage the claws if possible. The antennae were motionless, the 
scape lying alongside the rostrum. 

At Barnesville a beetle was observed ovipositing on plum, April 11. 
Its time record was as follows: 

Minutes. 
Beak inserted 9.47. 

Beak withdrawn and ovipositor inserted 9.49 , 2 

Ovipositor removed 9.49J § 

Packing cavity, until 9.52 2J 

Began cutting crescent 9.52 

Crescent completed 11.07 

Actual time occupied in cutting 36 

Beetle rested 6 times while cutting crescent, a total of 39 

Total interval , 80 

Also at Barnesville a beetle was observed April 20 ovipositing in 
young peach. At 9.30 the hole was started in fuzz, the beak being 
worked down full length. At 9.4 If beak was withdrawn and the 
ovipositor inserted. The ovipositor was withdrawn at 9.42£ and the 
egg pushed down with the beak. The beetle withdrew at 9.46 without 
filling the hole in the fuzzy covering of the peach as usual, the total 
time being 16 minutes. 

Another beetle, ovipositing on plum, inserted the beak at 9.08, the 
egg cavity was finished and ovipositor inserted at 9.09|, and the ovi- 
positor was removed at 9.10. After packing the egg cavity the 
crescent was begun, which was finished by 9.28, a total of 20 minutes 
for the entire process. 



LIFE HISTORY AND HABITS: THE ADULT. 



103 



EGG AND FEEDING PUNCTURES: POSITION ON FRUIT AND VARIATION 

IN FORM. 

The position of the egg puncture on the young fruit, as would be 
surmised from observations on the process of oviposition, is deter- 
mined in a general way by the part affording the beetles the best 
anchorage for their feet during the work of excavating the puncture 
and crescent. This position will vary according to the age of the 
fruit, and also according to the kind, as whether plum, peach, apple, 
or other species. Some data were secured by Messrs. Girault and 
Rosenfeld as to the location of egg and feeding punctures, which are 
set forth in Tables LII to LIV. In the case of the peach, it proved 
to be difficult to separate positively the two forms of punctures, and 
these are considered under the same heading. 

Table LII. — Location of egg and feeding punctures of the plum curculio on wild plums 

Myrtle, Ga., 1906. 





Fruits examined. 


u 

3 

a 

3 
ft 
be 

bo 


Location of egg punc- 
tures on fruit. 


CD 

H 

3 
o 

a 
& 

bo 

.9 

-3 
, <^ 

1 o 


Location of feeding 
punctures on fruit. 


Dates of examinations. 


CD 


From — 


» 


pq 


"3 

CD 
1 


H 

s 

O 
ft 


■6 

s 

pq 


a. 




as 
"w 

o 

cS 

a 
6 


-d 
id 

o 
ft 


■3 
.3 
.3 

pq 


Apr. 9 


200 
100 
100 
50 
50 
50 
50 
50 
50 
50 
50 
25 
50 


Tree 

...do 

...do 

Ground . . . 

Tree 

Ground . . . 
...do 

Tree 

Ground . . . 

Tree 

...do 

Ground . . . 

Tree 


22 
48 
55 
43 
76 

101 
52 
73 

102 
48 
62 
58 
42 

782 


22 
45 
49 
32 
36 
45 
13 
4 
17 
11 
8 
2 
2 

286 










11 

21 
3 

14 
5 

10 
6 
4 
5 
7 
3 
6 
3 

98 


2 

8 

"Y 

3 


"i" 

l 


4 
6 
1 
4 
1 


3 

6 
1 

.... 


9 


13 






2 
3 
4 
14 
21 
8 
3 
5 
8 
1 
1 
2 

72 


1 
3 
3 

19 
17 
25 
51 
46 
18 
34 
45 
17 

279 


1 


20 








22 


i 

2 
8 
2 
2 

14 
8 

14 
7 

18 

76 


3 
5 
10 
4 
13 
20 
3 
5 
3 
3 

69 


8 


30 


1 


30 


q 


May 8 








6 


8 




l 

2 
2 
1 


1 
1 
1 
1 

1 


~2 
13 


9 


31 


9 


31 


4 


June 6 


1 


6 


5 


11 






1 




14 


8 


21 




Total 


875 


49 









Table LIII. — Location of egg and feeding punctures of the plum curculio, Myrtle, 

Ga., 1906. 

KIEFFER PEAR. 





Fruits examined. 


CD 


Location of egg punc- 
tures on fruit. 


u 
3 

CD 


Location of feeding 
punctures on fruit. 












CD 










CO 






Dates of examinations. 


CD 

a 

3 


From— 


3 

a 

3 
ft 
bo 
bo 


X 

CD 

ft 


CD 


2 

"o 

t-i 

CD 
I 


-3 
H 
S 

ft 

< 


•6 

■3 
3 
PQ 


3 

ft 

bo 
3 
•3 


CD 

ft 

< 


CD 

pq 


s 



CD 

3 

6 


-3 

2 

ft 

<5 


■3 

M 

2 

pa 


Apr. 9 


200 
160 
100 
100 
50 
50 
50 
50 
50 


Tree 

Ground . . . 

Tree 

Ground . . . 

Tree 

Ground . . . 

Tree 

Ground . . . 
Tree 


16 

3 

20 

7 

40 
9 
26 
22 
16 

159 






8 

2 
13 

7 
24 

3 
11 
12 

8 

88 


2 
"3" 


6 
1 

4 


9 

5 

15 

8 

3 

1 

8 

12 

16 

77 


1 




5 
2 
11 
6 
3 
1 
6 
5 
6 

45 


3 

2 




9 






1 


13 










? 


13 






2 






20 : 






4 

7 
2 

24 


12 
3 
3 
2 
4 

35 






20 


3 


3 
3 
1 

2 

9 










May 2 






"3" 

1 

11 


? 


4 


1 
2 

6 


"2 

2 


3 


31 


a 






Total 


810 


13 









104 



THE PLUM CURCULIO. 



Table LIII. — Location of egg and feeding punctures of the plum curculio, Myrtle, 

Ga., 1906— Continued. 



APPLE. 





Fruits examined. 




Location of egg punc- 




Location of feeding 




w 


tures on fruit. 


CD 

3 


punctures on fruit. 




























Dates of examinations. 






3 
o 






3 

"55 


T3 
^ 


f-i 


ft 






2 

"55 


T3 

3 


-a 




at 

a 

3 


From — 


ft 


X 




o 


4^ 
3 


,3 


bo 

.9 
■a 


K 


CD 




<d 


"3 


,s 






bo 


ft 


03 


a 


ft 


c3 




ft 


cj 


d 


ft 


C3 




fc 




N 


< 


pq 


o 


<1 


« 


N 


< 


ft 


O 


■4 


W 


Apr. 13 


100 
50 
50 


Tree 

...do 

...do 


2 
15 

47 

64 






1 
6 

26 

33 


"7" 

7 


1 

5 
9 

15 


10 

8 
13 

31 




5 


4 
3 
1 

8 


1 
1 




22 


.... 
1 


4 
4 

8 


5 


May 5 




9 
14 


3 






Total 


200 


8 









Table LIV. — Location of egg -and feeding punctures of the plum curculio on peach, 

Myrtle, Ga., 1906. 





Fruits examined. 


■d 
s> 

c 
d 

3 
ft 

3 


& 

d 
3 
ft 

is 

60 
bo 


Location of egg and 
feeding punctures 
on fruit. 




Dates of examina- 
tion. 




From — 


X 

CD 
ft 
•< 




a 

pq 


CD 

s 

"o 
y 

V 

1 


t 

■a 

"3 


'ft 


13 
.3 
■g 

3 
§ 

03 


Remarks. 


Apr. 9 


200 
200 
100 
100 
50 
50 

50 
50 
50 

50 
50 
50 
50 
50 
50 


Tree 

...do 

...do 

...do 

...do 

...do 

Ground... 

Tree 

Ground . . . 

Tree 

Ground . . . 

Tree 

Ground . . . 

Tree 

Ground . . . 


4 
31 
20 
29 
19 
46 

46 
32 
37 

21 
34 
23 
35 
39 
43 


. 3 

42 
35 
63 
38 
111 

126 
122 
70 

36 
63 
45 
84 
122 
130 


"2 

3 
3 
2 
1 

12 
6 
1 

2 
7 
2 
3 
5 
20 


1 
7 
10 
3 
2 
4 

12 
10 
21 

6 
12 

6 
11 
12 
27 


1 
11 

7 
15 
20 
66 

60 
73 
15 

14 
24 
17 
46 
35 
30 


1 

8 
3 
4 
7 
15 

22 
11 

9 

4 
15 
11 
10 
35 
43 


"l4' 
12 

38 

7 

25 

20 
22 
24 

10 
5 
9 
14 
35 
10 


All feeding punctures. 


9 


4 egg punctures. 


13 


5 egg punctures. 


14 


21 egg punctures. 


20 


4 egg punctures. 


26 


Egg and feeding punctures not 


28 


separated. 
Do. 


May 7 


25 egg punctures. 


7 


Egg and feeding punctures not 


22 


separated. 
Do. 


22 -. 


Do. 


28 


Do. 


28 


Do. 


June 8 


Do. 


8 


Do. 






Total 


1,150 


459 


1,090 


69 


144 


434 


198 


245 











In the case of wild plums the tendency, early in the season when 
the fruit is small, to oviposit on the apex of the fruit is very 
marked. Thus to April 30, 55.8 per cent of all punctures were there 
located. After this date, by which time the fruit had become of 
some size, the egg punctures were to be found more often on the 
basal third. For the period of observations April 9 to June 11 the 
majority of feeding punctures was also found on the basal third. 
The distribution for the season of the totals is indicated in the table 
(Table LIT). 



LIFE HISTOKY AND HABITS: THE ADULT. 



105 



As' regards the Kieffer pear, there was always a majority of the egg 
punctures on the side, the basal third of the fruit being next pre- 
ferred, which distribution also holds good for the feeding punctures. 

Observations on apples were quite limited, but also indicate a pref- 
erence for the side for egg laying, while feeding punctures were about 
equally distributed over the base, side, and basal third, indicating a 
preference in feeding for the lower part of the fruit. 

At Barnesville, Ga., in 1910 it was observed that during the first 
10 days or 2 weeks of oviposition on the peach no punctures were 
made through the skin. Owing to the small area of the fruit surface 
at this stage of growth the layer of fuzz is very thick, and it seems 
that the snout of the beetle is not long enough to make the normal 
punctures when working through so great a depth of fuzz. Punc- 
tures were made in the fuzz 
down to the skin, which was 
usually abraded somewhat, 
causing a small area of russet 
to develop. The eggs were 
placed in contact with the fruit 
skin and the hole above them 
filled with loose fuzz. These 
punctures were conspicuous by 
reason of the difference in re- 
fraction between the normally 
erect pubescence and that 
which had been packed hap- 
hazard into an egg puncture. 

For peach the consolidated 
records of egg and feeding 
punctures for the season show 
a distinct majority in favor of 
the side of the fruit, with the basal third next in rank. 

The normal egg puncture consists of the egg cavity and a crescen- 
tic cut, as shown in figure 23. The egg cavity is cylindrical, about 
0.04 inch deep, and the crescentic cut is in the form of an arc. The 
egg cavity, and especially the crescent, may vary widely. The cres- 
cent, however, if it is to serve the purpose intended, is cut deeply and 
extends back under the egg cavity. (See fig. 23.) Externally the 
modification of the typical puncture usually consists of a shortening 
of the horns of the crescent, often to such an extent that the crescentic 
cut appears as a short straight line. Also the position of the crescent 
when of normal form varies much in relation to the egg cavity, which 
may be considerably to one side. These variations appear not to be 
due to faulty instinct, but to the different conditions under which the 
work is accomplished. Punctures made by individual beetles in con- 




FlG. 23. 



The normal plum-curculio puncture; egg at 
right. (Original.) 



106 THE PLUM CURCULIO. 

finement present many variations; as already explained, the beetles 
in making the punctures derive much of the necessary force from the 
legs, and the feet must be firmly anchored. That they often have 
trouble to secure a good footing is clear from observations on the 
beetles at work. In fact, the attempt at a given point on smooth 
and tough skinned fruits, as apples and plums, is not infrequently 
abandoned and other locations sought. Young apples and peaches 
covered with pubescence and pears with roughened skin afford good 
anchorage for the feet. As the apples grow, however, the skin 
becomes smooth and beetles have trouble in puncturing the tough 
skin and abnormal punctures are frequent. In the case of wild 
plums detailed observations indicate that difficulty is often expe- 
rienced by the beetles, as shown by variations in the egg puncture. 
Thus, in a study of 200 fruits which averaged about 12.75 mm. in 
greatest transverse diameter and each bearing an egg puncture, 102, 
or 51 per cent, of the punctures were normal. In 75 cases the crescent 
was short and almost a straight line and was entirely, absent in 23 
cases, the egg cavity only being present. The following records of 
the activities of 30 pairs of beetles in egg laying and feeding on plums 
during the night of May 12 are of interest in this connection. There 
were 121 crescentic punctures with eggs and 51 such punctures with- 
out eggs; 13 cavities with eggs were unaccompanied by crescents, 
and two eggs were found in one egg cavity. About 324 feeding 
punctures were present. 

The variation in position of the crescentic cut was found in 50 
plums examined to be as follows: Normal, 18; with crescent but 
little curved, 10; with crescent short and straight, 12; and the cres- 
cent was absent in 10. The same specimens showed a variation in 
relative position of crescent and egg cavity as follows : Egg cavity 
central to crescent, 20; slightly to right, 8; slightly to left, 5; on 
center of right, 4; on center of left, 3; crescent absent, 10. 

RELATIVE NUMBER OF FEEDING AND EGG PUNCTURES. 

The relative abundance of feeding and egg punctures was several 
times noted. Table LV gives data from three localities. The fruit 
used at Siloam Springs, Ark., was apple; at Washington, D. C, plum; 
and at Myrtle, Ga., peach. The date of death of the respective sexes 
was not determined for Arkansas. In the Washington records the 
dates are for both sexes, and the Georgia records give dates of death 
of each sex for each pair. 



LIFE HISTORY AND HABITS: THE ADULT. 



107 



Table LV. — Comparison of number of feeding and egg punctures of the plum curculio 

from various localities. 



l 

2 

3 

4 

5 

6 

7 

8 

9 

10 

Total 



Siloam Springs, Ark., 1908. 



Feed- 
ing 
punc- 
tures. 



549 
477 

85 
261 
195 
295 
267 

39 
409 
295 



2,872 



punc- 
tures. 



315 



Length of life. 



May 
May 
May 
May 
May 
May 
May 
May 
May 
May 



13 to Sept. 15. 
13 to July 28. 
13 to May 29. 
13 to June 28 . 
13 to July 8.. 
13 to Sept. 9.. 
13 to July 31 . . 
13 to May 24. 
13 to Aug. 20. 
13 to July 17. 



Washington, D. C, 1905. 



Feed- 
ing 
punc- 
tures. 



273 
311 
165 

280 



1,029 



Egg 
punc- 
tures. 



289 
616 
131 
350 



1,386 



Length of life. 



May 11 to July 3-6. 
May 11 to Aug. 28. 
May 11 to June 18. 
May 11 to July 7. 





Myrtle, Ga., 1906. 




Pair No. 


Feeding 
punc- 
tures. 


Egg 
punc- 
tures. 


Length of life. 


Male 
died — 


1 


160 
110 
217 
147 
152 
146 
150 
211 


138 
29 

191 
79 

118 
44 
82 

133 


Apr. 6 to July 30 


May 18 
July 29 
July 24 
July 20 
July 18 


2 


3 


Apr. 6 to July 26 

Apr. 6(?) 


4 


5 




6 


Apr. 6 to June 26 

Apr. 6 to June 18 

Apr. 6 to Aug. 10 


7 




8 


Aug. 20 




Total 


1,293 


814 









It will be noted that in two instances feeding punctures consid- 
erably outnumbered the egg punctures. For Arkansas the ratio 
is about 9 to 1 , and for Georgia about 1 \ to 1 , indicating considerably 
less feeding on peaches in proportion to egg laying than in the case of 
apples. The Washington records show a larger number of egg than 
feeding punctures, but these specimens were kept under temperature 
conditions abnormally high, which probably stimulated oviposition,' 
as elsewhere stated. 

ACTIVITY OF THE BEETLES IN EGG LAYING AND FEEDING, BY DAY 

AND BY NIGHT. 

Information on the relative activity during day and night of the 
beetles in oviposition and in feeding is meager. Riley x states that 
the curculio is nocturnal rather than diurnal, as regards the period of 
flight, and affirms that it is far more active at night than during the 
day. He further adds that, with the exception of such females as are 
engaged in egg laying, most of the curculios rest during the day, 
sheltered by the foliage or branches of the tree or convenient trash or 
the ground. 



1 Third Missouri Report, p. 14. 



108 



THE PLUM CURCULIO. 



In the article on the curculio by Riley and Howard/ it is stated that 
although the females lay their eggs chiefly during the daytime, the 
insect is essentially nocturnal, flying freely during warmer nights and 
only seeking shelter when the nights are cold. Prof. J. M. Stedman 2 
says that the females may deposit eggs during a part of the day and 
part of the night, or all day if the weather be cloudy, but do not appear 
to enjoy egg laying during the heat of the day. They frequently 
drop to the ground during the middle of the forenoon, hiding until 
late in the afternoon, when they fly to the trees and again begin work. 

In connection with other observations on beetles in confinement, 
Prof. Crandall determined the number of eggs and feeding punctures 
during day and night, respectively, winch data it would seem could be 
fairly held to indicate their general activity under normal conditions. 
Of the total of 5,631 feeding punctures recorded, 2,594 were made 
during the day and 3,037 at night, a balance of 443 in favor of night 
feeding. In regard to oviposition, of the total eggs recorded (1,954), 
1,037 were laid during the day and 917 at night (6.30 p. m. to 8.30 
a. m.), a balance of 120 in favor of the day for oviposition. 

Records made in 1906, at Myrtle, Ga., by Messrs. Girault and 
Rosenfeld bear out the conclusions evident from Crandall's observa- 
tions. April 9, beetles were captured by jarring peach trees and 
when found mating later in the day were separately confined in jars 
with wild plums. Beginning April 12, observations were made at 
9 a. m. and 9 p. m. each day until June 29, except in the case of pair 
No. 5, as shown in detail in Table LVI. After June 29 the records are 
not complete. 

Table LVI. — Comparative activity during day and night of five pairs of the plum curculio 
in feeding and oviposition, Myrtle, Ga., 1906. 





Pair No. 1. 


Pair No. 2. 


Pair No. 3. 


Pair No. 4. 


Pair No. 5. 


Dates of exami 
nation. 


Eggs. 


Feeding 
punc- 
tures. 


Eggs. 


Feeding 
punc- 
tures. 


Eggs. 


Feeding 
punc- 
tures. 


Eggs. 


Feeding 
punc- 
tures. 


Eggs. 


Feeding 
punc- 
tures. 




£ 


03 

A 


s 

ho 

£ 


>> 

03 

A 


2 

ho 

£ 


03 

A 


s 

bo 

£ 


03 

A 


i 

£ 


(A 

03 
A 


to 

£ 


03 

A 


+3 

■a 


03 
A 


s 

60 
£ 


03 

A 


ho 


(A 

03 

A 


s 

ho 

£ 


03 

A 


Apr. 10 










































11 


4 
4 
5 


~~2 

"4" 
1 
2 
4 
2 
2 
1 
10 
6 
2 
2 
5 

"5" 

7 


17 
8 
6 
7 
2 
5 
3 
5 
3 
4 
4 
2 
1 

~~3" 

7 
2 




































12 


7 
8 
3 
2 
2 
3 
2 
2 
1 
1 
6 
1 
4 
6 
2 
5 
5 






2 
1 
1 
1 
2 
3 
4 

6 
5 
8 
6 
4 
3 
2 
6 
7 
3 


1 

2 
1 
5 

5 






6 
5 

7 
1 
2 

"3" 
2 
6 
4 
3 
2 

3 
5 

6 


5 
4 
3 
2 
1 
1 
3 
1 
4 
1 
5 






4 
7 
8 
3 
3 
1 
5 
2 
4 
5 
2 
1 
5 
2 
2 
2 
3 


7 
6 
4 
2 
1 
3 








11 


13 


1 








1 

1 
1 
1 

2 


"4" 

3 
1 
4 
2 
5 
4 
1 
1 
2 


"3" 

.... 



2 
1 
1 

"2 


27 

10 

7 

6 

- 8 

5 

3 

2 

10 

1 

3 

2 

4 
6 


13 


14 


"4 

4 
2 
1 


7 
1 
5 
4 
3 
4 
3 
2 
1 
2 
3 


?, 


15 




.... 

2 

"2 

1 
2 
3 
2 
.... 

3 
5 
2 


3 
4 
3 
2 
1 
2 
4 
3 
1 
4 
.... 

4 
?, 


5 


16 

17 

18 


3 
3 
1 
2 
4 
.... 

3 
1 
3 
6 
4 
2 


2 
9 

?, 


19 






2 


20 


3 
5 
3 

""e>" 
4 
4 


.... 
.... 

1 


3 
3 
2 

4 

7 
9 
1 




2 


3 


21 


a 


22 . 






? 


23. .. 








24 


3 




2 
1 
1 

2 
1 


.... 

1 
4 


3 


25 




1 
4 
2 


3 


26 


"2" 

3 


2 
"2 


3" 

2 


2 


3 


27 


5 


28 


2 



1 Rept. Comm. Agr. for 1888, p. 61. 



2 Bui. 64, Missouri Station, p. 16. 



LIFE HISTOEY AND HABITS: THE ADULT. 



109 



Table LYI.— Comparative activity during day and night of five pairs of the plum curculio 
in feeding and oviposition, Myrtle, Ga., 1906 — Continued. 





Pair No. 1. 


Pair No. 2. 


Pair No. 3. 


Pair No. 4. 


Pair No. 5. 


Date of exami- 
nation. 


Eggs. 


Feeding 
punc- 
tures. 


Eggs. 


Feeding 
pune. 
tures. 


Eggs. 


Feeding 
punc- 
tures. 


Eggs. 


Feeding 
punc- 
tures. 


Eggs. 


Feeding 
punc- 
tures. 




4^ 

60 
g 


03 
ft 


5 

&o 

g 


>> 

03 

R 


3 

60 
g 


03 
ft 


2 

60 
g 


03 

ft 


i 

g 


03 
ft 


3 

60 
g 


03 
ft 


i 

g 


>> 

03 
ft 


5 

60 
g 


03 
ft 

4 
3 

1 
3 
2 
2 
3 
4 

1 
1 
3 


2 

ao 
g 

2 
3 

2 
2 
3 
1 
2 


>> 

03 
ft 

5 

3 

4 
5 
6 
1 


+3 

-a 
g 

3 
1 

4 
2 
4 
4 
1 
2 
4 

6 


>> 

03 

ft 




8 
1 


2 

7 

4 
3 
4 
2 
3 
5 
3 
4 
1 
3 
4 
3 
3 
2 
5 
5 
7 
4 
5 
5 
3 
4 
.... 

.... 


5 
2 

6 
12 

5 

3 

6 

2 

4 

1 

3 

4 

9 

4 

1 

3 

3 
10 

9 

7 
12 

7 

4 

2 

3 

6 
1 
2 
3 
5 
7 

8 
8 
6 
1 
1 
9 
5 
8 
6 
S 

"§" 

"8~ 
4 
5 
6 
6 


6 
5 

8 
8 
3 
5 
2 
5 
3 
3 
3 
1 
5 
.... 

3 
3 
3 
9 
4 
9 
6 
4 
2 
5 
3 
6 
3 
1 
5 
6 
6 
8 

"4" 
2 

1 
1 
C 
2 
3 
7 
7 
3 
5 


• 4 
3 

4 
3 
1 
3 
2 

2 
1 
2 

1 

"i" 

1 

"2 

1 

1 


6 
4 

4 
3 
2 
2 
1 
3 
1 
2 
1 
3 
1 
2 
2 
3 
2 
5 
3 


3 

10 
3 
4 
2 
1 
2 
6 
1 
1 
1 
1 
2 
1 
3 

"3" 
6 
2 

10 
5 
4 
1 
3 
2 
3 
2 
9 
1 
3 
5 
1 

5 
3 

4 
9 
8 
8 

7 
7 
6 


2 
3 

2 
7 
2 
1 
2 
1 
4 
2 
5 

"3" 

1 

1 
3 
4 
5 
4 

12 
10 
1 
7 
4 
1 
4 
10 
5 
6 
5 
4 

6 
4 
6 
8 
9 
7 
1 
6 
.... 

2 


2 

1 

5 
2 
3 
4 
2 
4 
1 
2 
1 
2 
2 
1 

"T 

1 
3 

"V 

2 
1 
1 






1 

5 

3 
5 
2 
2 
2 


"3 

2 
1 
3 
2 
2 
3 
2 
2 
1 
1 
3 
2 
4 
2 
2 
.... 

3 
1 
4 
1 


1 
1 
2 

"3" 

2 
2 

2 
1 


1 
1 

3 
2 
1 

2 

"4" 

1 

.... 

1 
2 
4 
2 
2 
1 
5 
5 
4 
5 
3 
1 
1 
.... 

1 

5 
3 
4 
2 
1 
1 


6 
4 

5 
4 
4 
2 
2 
5 
3 
1 
1 
3 
3 
6 

6 
5 
3 
3 
3 
9 
6 
5 
2 
3 
4 
8 
4 
4 
5 
2 
5 
7 

6 
6 
8 
3 
11 
9 
4 
3 
6 
5 
3 
.... 

1 
5 

4 
5 
4 

6 
7 
4 


4 


30 


1 
1 

"2 

2 
1 
2 
2 
3 
1 
1 
1 
.... 

.... 

"~6 

3 


2 

3 
3 
3 
2 
3 


5 




5 


2 


5 

4 
5 
1 
4 
5 
1 
o 

2 
1 
3 
3 
4 
4 

3 

2 
6 
6 
4 
1 
2 


4 


3 


1 


4 


3 


5 


2 




... 3 


3 


7 


1 
2 
1 
2 
4 
1 
1 
1 
2 
5 
2 
6 


2 

1 

"3 

1 
1 
1 
2 
2 
1 
4 
1 
1 
2 
.... 

1 
1 
3 
5 
3 
1 
5 
6 

2 
3 
5 
5 
3 




1 


1 




1 


9 






1 






2 
3 

3 

4 
5 
4 
2 
5 
1 
5 

"4" 

1 

4 

1 

5 
1 
3 
1 
13 
11 

3 

8 
2 

7 
5 
4 
3 
8 
3 
7 
41 


2 








4 


12 


2 
3 
5 
3 
6 
6 
4 
10 
7 
8 
4 
1 
7 
3 
5 
4 
6 
3 
5 
7 
2 
8 
1 
6 
7 
4 
2 

3 

7 
3 

1 
1 


1 

2 
1 
1 
1 
1 
.... 

3 
2 

"4" 
• 3 
3 
1 
1 
3 
1 
2 

4 
1 
2 
1 
2 
5 
2 
1 
2 
3 
5 
20 


"2 
1 

1 
2 
1 
3 
4 
4 
6 
3 
1 
4 
3 
4 
3 
2 
4 
3 

"'.V 
3 
6 
2 
3 
4 
3 
4 

3 


2 


13 


2 


14 


8 


15 


8 


16 




17 


6 


18 


I 


19 


3 

3 
1 

2 


3 

3 


"2 

1 
3 


1 


20 


1 
1 


7 
1 
5 
2 
1 
G 
1 
1 
3 
3 
1 
3 

5 
2 
2 
2 
3 
3 
2 
4 
3 


2 


01 


5 


22 


i 


23 




2 


1 


24.... 





25 


3 


2 


26 






1 


27 




1 
.... 

2 


.... 

1 
1 


4 


28 






"i" 


3 


3 


29 






1 


30 






3 


31 




2 

~3~ 
2 
1 

o 

3 

1 

.... 

1 
1 
3 

"2 
3 

.... 


1 

"2 

1 
1 


1 

"2 

3 

.... 

2 


3 


June 1 

2... 
Z......... 

4 


3 
3 

2 
1 
1 
2 
1 
1 
1 

1 
3 






2 


3 
1 
3 

1 
1 
2 
2 
2 
1 
1 


1 

1 

.... 

1 
.... 


3 

4 


1 


1 


1 


5 


6 


6 




1 


9 


7 


1 

1 

2 
2 


7 
1 


b 


8 


1 
2 


2 
1 


4 


9 


2 


10 


2 

1 

.... 

"6" 


.... 

"2 
2 




11 


1 


.... 


1 

1 






8 


12 . 


1 


"2 
1 
4 
2 
4 
5 

"4" 

2 
2 
5 
5 
3 
4 
6 


3 

4 

3 








1 






6 
7 
1 
2 
6 
1 
1 
7 
2 
5 








2 

2 

.... 

1 
"4" 


3 
5 
2 












4 
4 
1 
6 

2 






6 

5 
3 
2 
1 
1 


2 
2 

"3 

2 
3 
1 

2 


2 
.... 

3 

2 






















. 




















18 






1 
4 
1 


1 
1 


1 


1 






















20 
















21 




4 
2 
4 

"i" 

3 

""2" 
4 


"9" 
7 
6 

.... 

2 
2 
6 








1 


5 










oo 


3 
5 
3 

2 
2 
4 
5 
1 
























9 
6 
4 
3 
3 
7 
3 






1 




5 
2 

2 
1 
3 
9 












24 


















1 

1 

"Y 

7 


2 




4 
4 


1 




5 
4 

"5 

4 


1 

1 
2 


.... 


























1 
3 
2 


3 






















3 

2 


1 

7 












8 






1 






















































3 




58 




3 


3 

3 
9 




2 
5 
5 
4 






3 

1 


9 

7 


13 

6 




















6 




2 

5 


1 


1 


7 


3 






3 
3 
4 




14 




26 












12 








1 




1 










































18 
143 








Total 


204 


197 


381 


299 


92 


124 


298 


271 


101 


94 


219 


170 


97 


115 


328 


243 


124 


381 


210 



110 



THE PLUM CURCULIO. 



It will be noted that in the case of each of the five pairs, the num- 
ber of eggs deposited during the day is greater than the number laid 
at night. Of the total of eggs laid (1,291), 654 were laid from 9 a. m. 
to 9 p. m., while 637 were deposited during the balance of the 24 
hours, a difference, however, of only 17. A total of 2,800 feeding 
punctures is recorded, 1,607 being made at night and 1,193 during 
the day, a difference of 414 in favor of night feeding. 

The data suggest, therefore, that the curculio feeds rather more 
at night than in the day and that egg laying goes on at about an equal 
rate during night and day. 

TIME REQUIRED FOR TRANSFORMATION FROM EGG TO ADULT. 

The length of time spent in the fruit and in the soil has been shown 
separately in Tables XXV to XL. While these data are not entirely 
comparable, as representing different parts of the season and a 
variable number of individuals, nevertheless the final averages, when 
brought together, should give an approximate idea of the time 
required for the complete life cycle of the curculio. The final averages 
of time occupied in the fruit and in the soil as detailed are given in 
Table LVII with time for all stages shown, as determined by adding 
together these two periods. 

Table LVII. — Time required for the complete transformations of the plum curculio 
{combined data from preceding tables). 



Localities. 



Season. 



Time spent 
in fruit (egg 
and larval 
stages com- 
bined). 



Time spent 
in ground. 



Time re- 
quired for 
complete 
transfor- 
mation. 



Griggsville, III 

Youngstowri, N. Y., and North East, Pa. 

Washington, D. C : 

Myrtle, Ga 

Siloam Springs, Ark 

Douglas, Mich 

Barnesville, Ga 



1904 
1905-6 
1905-1908 
1906 
1908 
1910 
1910 



Days. 
20.00 
19.68 
15.52 
17.90 
21.74 
20.80 
20.73 



Days. 
28.24 
31.04 
32.04 
25.15 
29.00 
36.41 
34.38 



19.48 



30.89 



48.24 
50.72 
47.56 
43.05 
50.74 
57.21 
54.38 



50.27 



Considerable variation is shown between the averages of time spent 
in the fruit, and also between the averages of time spent in the ground, 
for the several localities. The shortest average time in fruit is shown 
by the 1905 Washington records, 15.52 days, and this is most closely 
approximated by the Georgia records a year later, namely, 17.90 days. 
The longest average is from Arkansas, in 1908, with 21.74 days. 
As regards the average time spent in the ground, the Georgia record 
for 1906 is lowest, 25.15 days, and the 1910 Michigan records highest, 
36.41 days, though closely approximated by the Barnesville records 
for 1910 of 34.38 days. 



TIME FROM EGG TO ADULT. 



Ill 



The average time required for complete transformation and 
emergence of beetles, as shown in Table LVII, also varies considerably, 
but in view of the variations in season and in the localities from which 
records were obtained are more uniform than had been expected. 
Thus, between the shortest time, 43.05 days (Georgia, 1906), and the 
longest, 57.21 days (Michigan, 1910), there is a variation of only 
14.16 days. The average time for the complete life cycle from egg to 
emergence of adult for all localities is 50.27 days. 

Complete records were obtained, in the case of a few individuals, of 
time occupied from deposition of egg to appearance of adult, as shown 
in Table LVIII. The averages for each locality are based on the 
total number of life-cycle days. The Barnesville, Ga., records include 
individuals from eggs laid each month from April to August, inclusive. 
These are separated in the table so as to show the marked lengthening 
of the life cycle in the earliest individuals, from eggs laid April 8-14. 

Table LVIII. — Showing time required for transformations of the -plum curculio from egg 
to adult. Individual records. 



Localities. 



Barnesville, Ga. 

Do 

Do 

Do 

Do 



Total. 



Youngstown, N. Y. 

North East, Pa 

Washington, D. C. . 

Myrtle, Ga 

Douglas, Mich 



Grand total. 



Dates of oviposition. 



Apr. 8-14, 1910.. 
May 9-26, 1910.. 
June lfi-30, 1910. 
July 1-30, 1910.. 
Aug. 7-17,1910.. 



June 21-24, 1905 

June 13-14, 1906 

May 10-June 10, 1905. 

May 7-16, 1906 "... 

June 24-July 6, 1910.. 



Indi- 
viduals. 



36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 



.307 



Beetles emerging in specified days 
from oviposition. 



2 1 

3 11 



5 12 



9 13 



3 

4 3 
12 15 



1 
25:21 



8 4 
2 1 

13 16 

7i 3 



1 
30 29 



Localities. 



Barnesville, Ga. 

Do 

Do 

Do 

Do 



Total. 



Youngstown, N. Y. 

North East, Pa 

Washington, D. C . 

Myrtle, Ga 

Douglas, Mich 



Grand total . 



Dates of oviposition. 



Apr. 8-14, 1910.. 
Mav9-26, 1910.. 
June 16-30, 1910. 
July 1-30, 1910.. 
Aug. 7-17, 1910.. 



June 21-24, 1905 

June 13-14, 1906 

May 10-June 10, 1905. 

May 7-16, 1906 

June 24-July fi, 1910.. 



Indi- 
viduals. 



415 

10 
17 
33 

24 



597 



Beetles emerging in specified days 
from oviposition. 



51 

"i 
3 

4 


52 

1 

5 
3 


53 

1 
4 
2 

7 

"i 


54 
3 

S 

1 
3 


55 

3 

3 

1 
19 


56 

2 
1 

3 
9 


57 

1 
1 
2 

4 
7 


58 

"i 

1 

4 


59 

3 

11 


60 

1 
1 
1 

3 

17 


61 

2 

1 
3 
1 

8 

12 


U2 

1 

1 


63 
11 

11 

7 

IS 


64 

12 

12 

2 

14 


65 
26 


s 

1 
3 

1 

1 


9 

1 
3 

"i 


26 

4 


14 


14 


8 


12 


23 


12 


11 


5 


" 


- 


30 



112 



THE PLUM CURCTJLIO. 



Table LVIII. — Showing time required for transformations of the plum curculio from 
egg to adult. Individual records — Continued. 



Localities. 


Dates of oviposi- 
tion. 


Indi- 
vid- 
uals. 


Beetles emerging in specified 
days from oviposition. 


Total 

life 

cycle. 


Aver- 
age 
length 




66 
17 


67 
8 


68 
7 


69 
3 


70 


71 
1 


72 
2 


73 


74 


75 


76 


77 


78 


of life 
cycle. 




Apr. 8-14, 1910 

May 9-26, 1910 

June 16-30, 1910... 

July 1-30, 1910 

Aug. 7-17,1910.... 


91 
49 
27 

177 
71 




1 


1 


Days. 
5,984 
2,327 
1,204 
7,979 
3,511 


Days. 
67.23 


Do... 


45.64 


Do 


44.59 


Do 


45.06 


Do 


49.53 






Total 


415 

10 
17 
33 
24 

98 


17 


8 
1 


7 
1 


3 




1 


2 








1 


1 


20, 995 

498 

832 

1,220 

1,086 

5,728 


50.35 




June 21-24, 1905... 
June 13-14, 1906... 
May 10-June 10,1905 
Mav 7-16, 1906 
Jurie24-July6,1910 


49.80 


North East, Pa 


43.06 




36.97 




45.25 




58.45 








597 


17 


9 


8 


3 




1 


2 










1 


1 


30,359 


49.85 









The several averages of time for complete transformations in the 
individual records show a range of from 36.97 to 67.23 days, the 
former from the insectary records of 1905 at Washington and the 
latter from Barnesville, Ga., in 1910. There is here a difference of 
30.26 days, but it should be borne in mind that the insectary records 
show a much shorter life-cycle period than normal, by reason of the 
high temperature under which the insects were reared. The average 
of all localities is 49.85 days, differing by only a fraction of a day from 
the average of 50.27 days already shown in Table LVII. 

SEASONAL HISTORY. 

TIME OP APPEARANCE OF BEETLES IN SPRING. 

The curculio is roused from hibernation in spring by about the same 
temperature conditions required to bring into blossom the various 
deciduous fruits upon which it subsists. It is a matter of importance, 
however, to know just when the beetles first appear in orchards with 
reference to the condition of the trees ; as whether before blossoming, 
during this period, or after the fruit has set. This question has a 
bearing on the time of making spray applications and of beginnirlg 
other remedial work, as jarring. Little exact information on this 
point is to be found in literature. Dr. Tilton (loc. cit., p. 116), 
writing in 1804, remarks that — 

Early in the spring, about the time when the fruit trees are in blossom, the cur- 
culiones ascend in swarms from the earth, crawl up the trees, and as the several fruits 
advance they puncture the rind or skin with their pointed rostra, and deposit their 
embryos in the wounds thus inflicted. 

Mr. William Bartram, in a paper read in 1789, expressed the belief 
that the insects appeared when the fruit was half grown or younger, 



TIME OF APPEARANCE OF BEETLES IN SPRING. 113 

and Dr. Harris (loc. cit., p. 67) remarks that they begin to sting 
plums as soon as the fruit is set. 

Dr. Fitch (Essay, p. 16), writing in 1860, states that the insects 
make their appearance on plum trees when the young fruit is about 
one-third or one-half grown. The question was well investigated by 
Dr. -Trimble (loc. cit., p. 72) in New Jersey in 1864, and frequent 
jarrings were made beginning May 12, at which time quince trees were 
in full bloom and green gage plums were just forming. Three beetles 
were caught from plum on May 13, 1 on May 18, and 10 on May 20 
on knots of cherry and plum. Curculio punctures were in evidence on 
pears and cherries on May 18 and on plum on May 19. 

Walsh (Prac. Ent., vol. 2, p. 75) states that the female curculio 
makes her appearance early in the season, and as soon as the young 
plums are a little larger than a hazelnut. 

According to Dr. Riley (loc. cit., p. 53) the beetles in central 
Missouri begin to enter orchards during the first days of May, and 
commence to penetrate the fruit about the middle of the same month, 
varying with the season, peaches at this time being about the size of 
a small marble. 

Riley (Amer. Ent., vol. 2, p. 131) further states that the curculio 
commences to puncture peaches when they are the size of small 
marbles or hazelnuts, though she may be found in the trees as soon 
as they are in blossom. 

_ This point is not touched upon in the excellent account of this 
msect by Riley and Howard in the Annual Report of the Commis- 
sioner of Agriculture for 1888, though in the colored plate accompany- 
ing the article the weevils are shown on a plum twig, the buds of 
which are not yet expanded. 

Lintner (11th N. Y. Rept., p. 122), writing in 1895, says that the 
plum curculio enters upon the scene at least two weeks before its 
first crescentic cuts are made in the fruit. 

More exact data are presented by Prof. Crandall (loc. cit., p. 495) 
in his studies of the curculio in Illinois, in 1903 and in 1904' Thus 
during the spring of 1903 apple trees were carefully searched at fre- 
quent intervals, but no beetles were found until May 10, when they 
were abundant, appearing to come all at once. Apple buds were 
opemng by April 16, the trees were in full bloom April 22 and the 
petals had practically all fallen by May 4. The beetles, therefore 
were not m evidence on the trees until a week after the blossoming 
period, coming suddenly in large numbers. In the spring of 1904 
systematic jarring of two trees was begun April 28. One beetle was 
taken from tree No. 1 on May 4, 1 on May 5, 5 on May 7, and subse- 
quently, a total of 15 by May 19. On tree No. 2 the first beetle was 
taken on May 17, and 1 the day following. On other trees beetles 
were taken May 7, and a few subsequently during the month. Apple 
. 17262°— Bull. 103—12 8 



114 



THE PLUM CUBCTJLIO. 



buds in 1904 were expending about May 3, trees were in full bloom 
May 10, and the blossoms had fallen by May 15. As compared with 
the condition of the trees, in 1904 the beetles were in evidence about 
two weeks earlier than in 1903. 

Some data have been obtained on this point by the Bureau of 
Entomology. In 1905 records were made by Mr. Johnson, at 
Youngstown, N. Y., (see Table LIX) and though jarrings were a little 
late, the results are of interest as showing the occurrence of insects 
with reference to the condition of the trees. 

Table LIX. — Time of appearance of plum curculio on trees in spring. Jarring records, 

Youngstown, N. Y., 1905. 



Dates trees 


Japan plum. 


Domestica 
plum. 


Peach. 


Pear. 


Condition of trees. 


jarred. 


Trees. 


Cur- 
culios. 


Trees. 


Cur- 

culios. 


Trees. 


Cur- 
culios. 


Trees. 


Cur- 
culios. 


May 11 

12 


50 
25 
25 

25 
50 
25 
25 
25 
15 
25 

25 


1 
9 
34 

1 

39 

9 

8 

6 

30 

26 

32 


25 
50 


2 
6 


25 
25 

25 

25 
25 
25 

25 
25 
15 
25 

25 










2 

2 

1 
1 

1 

4 
2 

2 








15 






Japan and Domestica 


16 

17 


25 
50 
25 

25 
25 
15 
25 


4 
23 
12 
7 
2 
11 
15 


25 




plums in full bloom. 


19 
22 
24 
27 


25 
25 
25 


2 
1 


Pears in full bloom. 
Plum blossoms fallen. 


30 






Peach and pear blossoms 








fallen. 


2 










First egg punctures seen 




















on apple and plum. 


Total 




195 




82 




15 




3 





Also, similar data were secured by Mr. Johnson at North East, Pa., 
in 1906, as shown in Table LX. 

Table LX. — Time of appearance of plum curculio on trees in spring. Jarring records, 

North East, Pa., 1906. 



Dates trees 


Sweet cherry. 


Sour cherry. 


Apple. 


Domestica 
plum. 


Condition of trees. 


jarred. 


Trees. 


Cur- 

culios. 


Trees. 


Cur- 
culios. 


Trees. 


Cur- 
eulios. 


Trees. 


Cur- 
culios. 


Apr. 30 .. 










25 








Cluster buds of apple 


May 2, . . 


50 
25 




50 


8 








just opening. 


25 

50 

50 
50 


1 

1 

6 

25 








g 












Sweet cherry and plum 


14 


25 
25 

25 

25 












trees in full bloom. 


16. . 








25 


1 




17 


1 


25 

25 
25 


17 

7 
7 


Sour cherry in full 


20 


25 


25 






bloom. 


28 






First egg punctures on 
















plums, pears, apples, 
and cherries seen May 
24. 


Total 




1 




39 




58 




1 





TIME OF APPEARANCE OP BEETLES IN SPRING. 



115 



The same year (1906) Messrs. Girault and Rosenfeld investigated 
this point in Georgia. In addition to the trees jarred, as shown in 
Table LXI, various trees in the woods, as Crataegus, wild plum, etc., 
were also jarred, but without results. 

Table LXI.— Time of appearance of plum curculio on trees in spring. Jarring records, 

Myrtle, Ga., 1906. 





Wild plums 
in thickets. 


Peach. 


Japan plum 


Pear. 


Apple. 




Dates tress 
jarred. 


0> 


"3 

o 

o 


0) 


.9 
"3 

o 

U 
o 




.2 

"3 

H 

3 
O 




3 
o 


a3 

M 
EH 


"3 

o 

u 

3 

o 


Condition of trees. 


Feb. 23.... 


Many. 

Many. 
Many. 

Many. 
Many. 

Many. 
Many. 
Many. 

Many. 
Many. 
Many. 

Many. 


~~2 


Many. 

Many. 
Many. 

Many. 
Many. 

Many. 
Many. 
Many. 

Many. 
Many. 
Many. 

Many. 
Many. 
Many. 




Many. 




Many. 








A few peach and wild 
plum blossoms open. 


Mar. 5 








9.... 
















Wild plum trees in full 
bloom. 


12.... 
















14.... 


~5 


Many. 

Many. 
Many. 
Many. 

Many. 

Many. 












Pears about in full bloom; 
Elberta peaches in full 
bloom. 


16.... 












18.... 




Many. 
Many. 

Many. 
Many. 
Many. 

Many. 










21.... 








Blossoms fallmg from 
peach, pear, and plum. 


23.... 








24.... 


4 








25 






Peaches, pears, and 
plums well set. 


26.... 


1 

3 
4 












28.... 














29.... 


Many. 


















30.... 


Many. 


1 












Apr. 4 














A few. 


2 


Apples in full bloom. 


11.... 






1,000 
1,000 
1,000 


227 

422 
88 

750 










13.... 




















16.... 
























2 








4 








Total. . . 




2 

















At Siloam Springs, Ark., in 1908, jarring records were made in a 
peach orchard as shown in Table LXIL 

Table LXIL— Time of appearance of beetles on trees in spring. Jarring records, Siloam 

Springs, Ark., 1908. 



Dates trees 
jarred. 


Trees. 


Curculios. 


Condition of trees. 


Mar. 18 


950 

950 
950 




— 

Pears, cultivated plums, and peaches in full bloom; cluster buds on 

apple showing. 
Petals mostly down from peaches, pears, and cultivated plums. 


26 




28 


6 


30 


950 
950 
950 
950 






31 

Apr. 2 


2 


Ben Davis apples nearly in full bloom. 

First feeding punctures by caged beetles on peach. 


4 


1 


6 


950 


1 




S 

11 

13 


950 

950 
950 


42' 

17 
13 


Petals mostly down from apples, cherries, and wild plums; calyces 

beginning to shed from peaches. 
First feeding punctures on peaches in orchard. 


14 

15 


950 
950 


8 
13 


First egg punctures in plums. 


17 

20 


950 
950 


64 
146 


First egg punctures in peaches. 


22 


950 


169 

1 


Calyces entirely shed from peaches. 



116 THE PLUM CUECULTO. 

At Olden, Mo., in the spring of 1907, beetles were out unusually- 
early owing to a protracted warm spell. On March 26, a few feeding 
punctures were found on Kieffer pear and on newly set cherries. 
On the same date, egg and feeding punctures were noted on recently 
set plums. An examination of 200 young plums from an isolated 
tree gave sound fruit 186, 2 with egg punctures, and 12 with feeding 
punctures, the fruit being from 3 to 4 mm. in diameter, and the 
calyces just dropping off. Jarrings made on March 27, of wild plum, 
cherry, peach, and pear, gave only 3 adults, all from cherry, with 
fruit barely set. April 4, 30 adults were captured by hand from 
seedling pear located near peach trees, and about as many beetles 
escaped. None was found feeding on adjacent apple and peach 
trees. The condition of the fruit trees at this place is shown by the 
following: March 24, cherries were in bloom; wild plums well set; 
petals of Elberta peach and Kieffer pears mostly fallen. March 26, 
Gano apples were in about one-third full bloom and Ben Davis trees 
were showing first bloom. 

In the vicinity of Washington, D. C, in 1905, a single beetle was 
taken April 27, and 4 specimens were jarred from peach on the day 
following. First punctured fruit (plums) was observed May 4, at 
which time it was about the size of a small bean. Punctures in fruit 
were increasingly in evidence after this date. Peach and pear trees 
were in full bloom that year by April 14 and apple trees by April 21. 
Native and Japanese plums were in full bloom by April 10, and 
earlier. 

On May 2, 1906, a single beetle was captured in the insectary yard, 
at Washington, on plum. A jarring of 7 peach trees, May 4, gave 14 
curculios, and from 8 plum trees 122 beetles were taken. The peaches 
at this date were just shedding the calyx shucks, and plums were | 
of an inch in diameter. On May 16 curculios were very abundant on 
peach and plum, a thousand being caught in jarrings from 6 a. m. to 
10 a. m. Peach, plum, and pear were in full bloom by April 14 and 
apple by May 1. 

In 1908, pear trees were in full bloom by April 9, while peaches and 
plums had dropped most of their petals by this date. Apple trees 
were mostly in full bloom April 24. The first signs of the curculio 
were noted April 24, when beetles were found feeding upon plum 
foliage, and additional specimens were found on plums April 27. 

Jarring records were made in the spring of 1910 at Barnesville, Ga., 
North East, Pa., and Douglas, Mich., all in peach orchards. The 
relation of the appearance of beetles to the condition of the trees at 
these places is shown in Tables LXIII, LXIV, and LXV. 



TIME OF APPEABANCE OF BEETLES IN SPUING. 



117 



Table LXIII. — Time of appearance of beetles on trees in spring. Jarring records , 

Barnesville, Ga., 1910. 



Dates trees 
jarred. 


Trees. 


Curculios. 


Condition of trees. 


Mar. ID 

14 

16 

18 

21 

23 

25 

28 

30 

Apr. 1 

4 

6 

8 


336 
336 
336 
336 
336 
336 
336 
336 
336 
336 
336 
336 
336 


19 
9 
1 
5 

20 
483 
840 
1,071 
563 
534 
427 
243 
166 


Scattering blossoms open on Elberta peaches. 
Elberta peaches in full bloom. 
Ked June and Abundance plums in full bloom. 
Carmen peaches in full bloom. 

Petals fallen from Elberta peaches; first egg punctures in plums. 
Petals fallen from Carmen peaches. 
Peaches bursting through calyces. 



Table LXIV. — Time of appearance of beetles on trees in spring. Jarring records, 

North East, Pa., 1910. 



Dates trees 
jarred. 


Trees. 


Curculios. 


Condition of trees. 


Apr. 15 


75 
75 
75 
75 
75 
75 
75 
75 
75 
75 
75 
75 
75 
75 
75 
75 


3 


Less than 5 per cent of peach blossoms open. 
About 75 per cent of peach blossoms open. 


20 


22 




26 




Peaches 90 per cent in full bloom. 
Peaches shedding some petals. 


28 




May 2 




4 




Nearly all petals fallen from peaches. 
All petals fallen from peaches. 


6 




9 


7 


11 




13 


1 




16 




19 


5 
19 
22 
22 




21 

23 


Peaches beginning to burst calyces. 
A few calyces falling. 
Many calyces falling. 


26 





Table LXV. — Time of appearance of beetles in spring. 

1910. 



Jarring records, Douglas, Mich. 



Dates trees 
jarred. 


Trees. 


Curculios. 


Condition of trees. 


May 4 






Apr. 25, Elberta peaches, pears, and sweet cherries shedding petals. 


7.... 


...do 


2 
3 
2 
3 

15 
115 

58 

67 

57 

74 

82 

97 

94 
315 
350 
114- 
103 


10 


...do.. 




13 

16 


...do.... 
.do. 


Apr. 30, sour cherries in blossom; also apples. 


19 


.do 


24 


...do.. 




26 


..do. 


May 3, Bartlett pears in blossom; also some peaches. 


28 


.do 




.do 


May 4, Baldwin apples in full bloom. 


3 


...do... 


6 


...do.. 


May 10, Spitzenberg apples in full bloom. 


9 


.do.. 


12.... 


.do 




15 


...do... 




18 


...do... 




21 


...do 




24 


...do... 











From the foregoing data it appears that the curculios usually first 
appear on the trees each season at nearly the same time relative to 
the advancement of fruit trees, namely, during or a little before the 



118 



THE PLUM CUKCULIO. 



blooming period of apples or shortly after the petais of peaches, pears, 
and plums have fallen. In some seasons, however, the curculios may 
appear as early as the blooming period of the plum or be retarded 
until after apples have shed the petals. Thus it appears that the 
beetles are affected by temperature to a different degree than are the 
plants on which they live. Probably the curculios are more sensi- 
tive to short periods of warmth and less so to longer periods at a 
somewhat lower temperature. 

RELATION OF TEMPERATURE TO APPEARANCE OF BEETLES. 

A comparison of the numbers of beetles caught in jarrings with the 
average daily mean temperature immediately preceding each jarring 
furnishes information on the temperature necessary to bring the 
beetles out of hibernation. Such data are available from Youngs- 
town, N. Y., for 1905; Siloam Springs, Ark., for 1908; and from 
Barnesville, Ga., North East, Pa., and Douglas, Mich., for 1910. 
These are given in Table LXVI. 

Table LXVI. — Jarring records showing relation of temperature to appearance of beetles 
of the plum curculio from hibernation. 



Barnesville, 


Ga. 


Siloam Springs, Ark. 


North East, Pa. 


Douglas, Mich. 


Youngst 


own, IT. Y. 




d a> 






O SJ 






a ® 






9, 






a 03 






£ 2 

g.a 
a » 






=« 2 

03 3 

a -a 






<s 2 
oj 3, 

g-3 






<a 2 

03 3 

g-3 






§.a 

a to 






t>> m 






>> M 






fc-. m 






hvi 






>>„ 






?3 03 






a 8 






S3 03 


^ 




:3 03 












<B 03 03 


fi 




03 0) o3 


,s 




o ^C 

03 03 o3 


,3 




31 £ 

° 2 1! 

03 03 § 


xi 




03 s- j,; 


fl 


Dates. 


6J0 

3 
03 
CJ 


Dates. 


be 
3 
03 
O 


Dates. 


60 

3 
03 
o 


Dates. 


to 

3 
03 




Dates. 


<-> ii 

03 B 


60 

D 
03 
CJ 




60R.2, 






bca-S, 






2f & -™ 


GO 




6C&.S, 






6DP..2, 


to 




28s 


£3 




03 £ +j 

M P. m 


"*3 




03 rt+i 

Srt R "i 


5 




say 


£< 




|a-K 


;2 




g oj as 






£> 03 o3 


03 




f»c) 


03 




££.2 


03 




PjS ea 


03 




> +J-H 


s> 




>+ J — < 


03 




> **— • 


Ov 




03 






03 




< 


m 




< 


n 




< 


FQ 




< 


n 




■5 


« 


1910. 


"F. 




1908. 


°F. 




1910. 


°F. 




1910. 


°F. 




1905. 


OJ1 




Mar. 10 


€3 


19 


Mar. 28 


69 


6 


Apr. 15 


43 


3 


May 7 


44 


2 


May 11 


54 


3 


14 


55 


9 


30 


48 




20 


52 




10 


52 


3 


12 


50 


17 


16 


47 


1 


31 


52 


2 


22 


39 




13 


46 


2 


15 


57 


36 


18 


50 


5 


Apr. 2 


61 


.... 


26 


45 




16 


45 


3 


16 


59 


6 


21 


57 


20 


4 


43 




28 


45 




19 


54 


15 


17 


59 


63 


23 


59 


483 


6 


52 


1 


May 2 


50 




24 


60 


115 


19 


56 


21 


25 


67 


840 


8 


64 


42 


4 


53 




26 


52 


58 


22 


50 


18 


28 


69 


1,071 


11 


56 


17 


6 


41 




28 


48 


67 


24 


50 


9 


30 


71 


563 


13 


53 


13 


9 


49 


"Y 


June 1 


51 


57 


27 


59 


45 


Apr. 1 


70 


534 


14 


61 


8 


11 


51 


.... 


3 


44 


74 


30 


56 


43 


4 


71 


427 


15 


62 


44 


13 


40 




6 


53 


82 


June 1 


52 


34 


6 


71 


243 


17 


66 


64 


16 


40 




9 


50 


97 








8 


65 


166 


20 


64 


146 


19 


62 


"5" 


12 


59 


94 








11 


62 


169 


22 


66 


169 


21 


60 


19 


15 


63 


315 








13 


68 


95 


24 


65 


75 


23 


66 


22 


18 


70 


350 








15 


64 


69 


27 


60 


10 


26 


61 


22 


21 


69 


114 








18 


64 


72 


30 


46 


16 


28 


50 


1 


24 


75 


103 








20 


56 


12 


May 2 


51 


41 


30 


60 


19 


27 


72 


47 








22 


54 


53 


5 


64 


13 


June 2 


46 


4 


30 


68 


145 








25 


59 


15 


9 


54 


28 


4 


50 


13 


July 4 


74 


105 








27 


46 


16 


12 


62 


57 


6 


50 


6 














29 


55 


90 


14 


67 


15 


8 


51 


4 














May 2 


70 


125 


21 


72 


91 


10 


56 


31 














4 


73 


82 


25 


71 


193 


13 


57 


13 














6 


67 


52 


27 


74 


198 


15 


64 


19 














9 


66 


29 


30 


70 


87 


16 


67 


37 














11 


65 


101 








18 


66 


19 














13 


73 


31 








20 
22 
25 
27 
29 


67 
70 
69 
67 

68 


28 
26 
21 
19 
18 















TEMPERATURE AND APPEARANCE OP BEETLES. 



119 



The effect of temperature in these records is obscured to a con- 
siderable extent by other conditions that affect the number of beetles 
caught by jarring, as winds, rains, proximity to hibernating grounds, 
and number of beetles previously caught. But the data seem to show 
that some beetles will become active at a mean temperature of 55 to 60° 
extending over three or four consecutive days, and that a mean 
temperature above* 60° for several successive days will bring out the 
beetles en masse. After the beetles have once come out of winter 
quarters they may be-jarred from the trees following periods with a 
mean temperature much below the degree required to bring them 
into activity, though such periods of cold weather greatly reduce 
the numbers caught. In Table LXVII is given a summary of the 
data in Table LXVI, showing the number of beetles caught at 
different temperatures for all five localities. 

It will be seen from this table that beetles have been jarred in 
considerable numbers following days with an average mean tem- 
perature below 55° and even below 50°. But by a study of Table 
LXVI it would seem that these beetles had been brought out by 
earlier spells of warmer weather and were already on the trees when 
the temperature dropped immediately preceding the jarrings. Prob- 
ably a mean temperature of between 55 and 60° is required to cause 
the beetles to leave their hibernating quarters. 



Table LXVII. 



-Number of beetles of the plum curculio jarred at different temperatures, 
all localities combined. 



Average 
daily 
mean 

tempera- 
tures 

since last 

jarring. 


Jarrings. 


Beetles 
caught. 


Average 
beetles 
per jar- 
ring. 


Average 
daily 
mean 

tempera- 
tures 

since last 

jarring. 


Jarrings. 


Beetles 
caught. 


Average 
beetles 

per jar- 
ring. 


°F. 
39 
40 
41 
42 
43 
44 
45 
46 
47 
48 
49 
50 
51 
52 
53 
54 
55 
56 


1 

2 
1 






°F. 

57 
58 
59 
60 
61 
62 
63 
64 
65 
66 
67 
68 
69 
70 
71 
72 
73 
74 
75 


3 


69 


23 


1 


i 


6 
4 
2 
3 
2 
6 
3 
5 
6 
3 
4 
5 
4 
2 
2 
2 
1 


706 

351 

22 

221 

334 

361 

342 

301 

991 

258 

1,212 

1,122 

1,426 

138 

113 

303 

103 


118 

88 

11 

73 

167 

60 

114 

60 

165 

86 

303 

224 

356 

69 

56 

151 

103 






2 
2 
3 
4 
1 
2 
1 
9 
4 
6 
3 
4 
2 
5 


4 

76 

3 

3S 

1 

68 

7 

166 

102 

98 

95 

99 

99 

124 


2 

38 

1 

9 

1 

34 

7 

18 

25 

16 

32 

25 

49 

25 



120 



THE PLUM CTTBCTJLIO. 



OCCURRENCE OF BEETLES IN ORCHARDS. 

The relative abundance during the season and the distribution of 
the beetles in orchards are shown to a certain extent by jarring 
records. Several such records have been obtained, beginning the 
work of jarring quite early in the spring and continuing at short 
intervals until the gathering of the fruit crop, oii later. The early 
portions of the following records, with additional ones, have been 
given in connection with the consideration of activity of beetles in 
spring. 

Table LXVIII gives the results of jarring 950 Elberta peach trees, 
at Siloam Springs, Ark., for the period from March 28 to June 27, 
1908. This block of trees was used to determine the value of jarring 
in protecting the fruit from injury, as referred to on page 174. 

Table LXVIII. — Jarring record for the plum curculio on peach, Siloam Springs, Ark., 

1908. 



Dates of 


Beetles 


Dates of 


Beetles 


jarring. 


caught. 


jarring. 


caught. 


Mar. 28 


6 


May 2 


41 


30 




5 

9 


13 

28 


31 


2 


Apr. 2 




12 


57 


4 


1 


14 


15 


6 


1 


21 


91 


8 


42 


25 


193 


11 


17 


26 


20 


13 


13 


27 


198 


14 


8 


33 


87 


15 


44 


June 3 


76 


17 


64 


5 


112 


20 


146 


11 


131 


22 


169 


15 


96 


24 


75 


17 


107 


27 


10 


19 


84 


30 


16 


22 


118 






27 


128 






Total . 


2,209 



The spring, on the whole, was late, there being much cool and 
rainy weather. The beetles were notably scarce, only 2,209 insects 
being captured during the period of jarring, an average of about 2.3 
beetles per tree. Considerable variation in the number captured on 
successive dates of jarring is to be noted. Thus, on May 25, 193 
beetles were taken, and the following day only 20. The record 
indicates the erratic behavior of the beetles due, it is believed, to 
weather conditions, but shows that by April 8, beetles were out in 
numbers, the maximum emergence occurring during late May and 
during June, with a smaller maximum about the third week in April. 

In Table LXIX are shown results from jarring a block of 75 peach 
trees at North East, Pa., during 1910. The trees were in sod and 
had never received treatment for the curculio. They were jarred 
every other day, unless weather conditions prevented, beginning April 
15 and ceasing September 2. The three specimens captured April 15 



BEETLES IN ORCHAEDS. 



121 



indicate a very early movement of the beetles for that locality, 
though no more were taken until May 9, more than three weeks later. 
Activity of the insects did not properly begin until May 21, after 
which date, with the exceptions shown, they proved to be fairly 
uniform in numbers up to July 2; after the latter date lew were 
captured. A total of 381 individuals was taken during the period, 
an average of 5 and a small fraction per tree. 

Table LXIX. — Jarring record of the plum curculio on peach, North East, Pa., 1910. 



Dates of jarring. 



Apr. 15 


3 


20 




22 




26 




23 




May 2 




4 




6 




9 


7 


11 




13 


1 


16 




19 


5 


21 


19 


23 


22 


26 -.- 


22 


23 


1 


30 


19 




4 


4 


13 


6 


6 


8 


4 


10 


31 


13 


13 


15 


19 


16 


37 


18 


19 



Number 
of beetles 
caught. 



Weather condi- 
tions. 



Cloudy. 

Do. 
Fair. 
Cloudy. 
Fair. 
Foggy. 
Clear. 

Do. 
Cloudv. 

Do. 
Clear. 

Do. 

Do. 
Partly cloudy. 

Do. 
Clear. 

Do. 
Cloudy. 

Fair. 

Partly cloudy. 

Clear. 

Partly cloudy. 

Do. 
Clear. 

Partly cloudy. 
Clear. 



Dates of jarring. 



June 20. 
22. 
25. 
27. 
29. 
July 2. 

5. 

7. 

9. 
11. 
13. 
16. 



23. 

26. 

29. 

Aug 2. 

5. 

11. 

16. 

22. 

26. 

30. 

Sept. 2. . 



Total. 



Number 
of beetles 
caught. 



381 



Weather condi- 
tions. 



Clear. 

Do. 

Do. 
Cloudy. 
Clear. 

Do. 

Do. 
Cloudy. 
Clear. 
Partly cloudy. 

Do. 
Clear. 

Do. 
Partly cloudy. 

Do. 
Clear. 

Do. 
Partlv cloudy. 
Clear: 

Do. 
Foggy. 
Partlv cloudy. 

Do. 

Do. 



In the jarring records obtained during 1910, at Douglas, Mich., a 
block of 70 peach trees was used, and the number taken on each row 
at each jarring was separately recorded. Row No. 1 was adjacent 
and parallel to a piece of woodland, the influence of which is evident 
by the larger number of insects taken early in the season from the 
first two or three rows. After about June 9 the beetles were uni- 
formly disseminated over the whole block. From May 4 to 10, a 
total of 5 beetles was secured and from May 13 to 19, a total of 20. 
From the last date they put in an appearance rapidly, showing for 
the period from May 24 to 28 a total of 240. The beetles were in 
maximum abundance during June, which month yielded 1,468, or 
59 per cent of the total for the season. The insects, nevertheless, 
were quite generally present all through July and August. None 
was taken after August 31, though jarrings continued until Septem- 
ber 19. (See Table LXX.) 



122 THE PLUM CURCULIO. 

Table LXX. — Jarring record for the plum curculio on peach, Douglas, Mich., 1910. 



Dates of jarring. 


Curculios caught fcy rows. 


Total. 


Row 1. 


Row 2. 


Row 3. 


Row 4. 


Row 5. 


Row 6. 


Ma 4 
















- >j 




1 
1 


1 
1 








2 






1 






3 




1 
1 

5 

33 

19 

21 

12 

25 

22 

31 

18 

S4 

67 

22 

19 

10 

12 

9 

8 

7 

13 

3 

5 

2 

3 

1 

2 

3 

1 

6 

6 

8 

1 

3 

3 

6 




1 

12 

2 

3 

3 

6 

7 

11 

13 

25 

20 

13 

6 

2 

14 

10 

2 

2 

11 

14 

3 
1 

1 
4 
7 
7 
3 
6 
6 
2 
5 


2 










2 
3 
4 
2 
5 
1 
2 
19 
11 
12 
51 
40 
15 
9 
10 
27 
13 
2 

6 
33 
18 
8 
3 
7 
4 

6 
9 
9 
12 
9 
4 
4 
w 


3 


19 


6 
39 
22 

26 

21 

20 

18 

25 

20 

87 

85 

27 

21 

11 

41 

27 

14 

5 

19 

5 

8 

9 

9 

9 

6 

4 

2 

8 

5 

3 

2 

14 

1 

3 


1 

19 

7 

8 

9 

16 

11 

8 

16 

37 

87 

19 

25 

11 

25 

36 

6 

4 

17 

23 

8 

9 

7 

5 

1 

3 

16 
S 
11 
11 
14 

2 


8 

6 

4 

1 

5 

5 

11 

15 

31 

51 

18 

23 

- 3 

26 

10 

1 

7 
13 
6 
12 
8 
6 
1 
5 
2 
3 
10 
8 
8 
7 
3 


15 




115 


26 


58 


23 


67 




47 


3 


74 


6 


82 


9 


97 


12 


94 


15 


315 


18 


350 


21 


114 


24 


103 


27 


47 


30 


145 


July 4 - 


105 




32 


9 


19 


12 


73 


15 


91 


18 


45 


21 


40 


25 


33 


27 


29 


30 


14 




13 




12 


10 


46 


13 


45 




42 




40 


24 


53 


27 


13 


31 


20 







By far the most complete record, however, was obtained at Barnes- 
ville, Ga., during 1910 (see Table LXXI). This work was accom- 
plished by Mr. E. W. Scott, though completed during the latter part 




cont/wation or paten orchard— sprayed byohwer. 



,,,r^ 7 :,^^. 



HOUSE -we LOT 



JARRED BLOCK- 33£ TRECS. 



o o f o e o o ® © ® © o 
H™i £ \ o « c ooo » o 
£ © o °\^ *"o H 75 S K ? e o © © © | o 
& & 1 Wo"o O^O o o o o o 

& 4°. .IWrtW. . hi i I • • 
i I . Vy; 2 . 3 * 7 ^;? o o . o . . « 
4i.. \W^'W?.i4*i. . 




7^ 



WHCAIT r/CU3 



Fig. 24.— Diagram of portion of peach orchard used in jarring experiments against the plum curculio 
Barnesville, Ga., 1910. (Original.) 

of the season by the junior author. Ten rows of Elberta peach trees 
were used, paralleling a piece of woods. B,ow No. 1 was separated 
from woods by only a wagon road. A total of 336 trees was jarred, 
all as indicated in the diagram (fig. 24). As shown in the figure, a 
terrace covered with grass and weeds bordered all of the rows on the 



BEETLES IN OBCHABDS. 



123 



east, and extended between rows Nos. 9 and 10. Excepting a check 
of 60 trees extending across the 10 rows on the west end, the trees 
surrounding the jarred block to the east and north were sprayed by 
the owner with arsenate of lead in self-boiled lime-sulphur wash. 

Table LXXI. — Jarring record for the plum curculio on peach, Barnesville, Ga., 1910. 









N 


umber of curculios caught, by rows. 








Dates of 
















Total 


jarring. 


























Row 1. 


Row 2. 


Row 3. 


Row 4. 


Row 5. 


Row 6. 


Row 7. 


Row 8. 


Row 9. 


Row 10. 




Mar. 10. 


16 
5 


1 
1 

1 
1 

27 


2 










1 






19 


14 




1 






1 


1 


9 


16 












1 


18 


3 

15 

406 
















1 

1 
15 


5 


21 


1 

10 


1 
6 




1 
6 








20 


23 


7 


1 


5 


483 


23 


460 


140 


56 


45 


32 


13 


14 


15 


16 


49 


840 


28 


550 


125 


95 


58 


38 


33 


30 


33 


35 


74 


1,071 


30 


206 


77 


57 


36 


21 


24 


29 


21 


38 


54 


563 


Apr. 1 


186 


74 


54 


33 


18 


19 


23 


18 


54 


55 


534 


4 


92 


38 


45 


39 


32 


29 


37 


21 


45 


49 


427 


6 


93 


36 


38 


17 


10 


3 


2 


6 


10 


28 


243 


8 


71 


23 


21 


5 


3 


4 


3 


6 


9 


21 


166 


11 


54 


30 


16 


6 


9 


10 


13 


7 


7 


17 


169 


13 


34 


13 


14 


4 


3 


2 


5 


3 


6 


11 


95 


15 


31 


8 


8 


3 




3 


3 


1 


3 


9 


69 


18.".... 


22 


10 


8 


4 


3 


3 


5 


2 


5 


10 


72 


20 


5 
9 


2 
11 


5 


1 

5 












4 

8 


12 


22 


2 


2 


1 


3 


7 


53 


25 


5 
3 


4 


1 
1 


3 
1 


1 






1 


2 
1 


2 

1 


15 


27 


3 


2 


16 


29 


23 


8 


9 


4 


2 


2 


2 


4 


10 


26 


90 


May 2 


41 


21 


13 


3 


7 


3 


7 


6 


10 


14 


125 


4 


33 


5 


5 


4 


4 


2 


6 


2 


6 


15 


82 


6 


12 


3 


5 


1 


3 


3 




2 


10 


13 


52 


9 


7 
39 


5 
14 


1 

3 


2 
6 


4 


1 

2 






8 
9 


5 

8 


29 


11 


8 


8 


101 


13 


13 


3 


1 




1 


1 


1 




5 


6 


31 


16 


4 
6 
37 


1 

1 

11 


3 
9 


2 
5 


1 




1 
2 
6 








10 


18 


1 
4 


' 2 
9 


4 
11 


18 


20 


2 


4 


98 


23 


23 


6 


6 


3 


3 


1 


2 


1 


4 


12 


61 


25 


18 


2 


3 


4 


3 




1 


2 


4 


4 


41 


27 


15 


10 


3 


3 


2 


3 


1 


2 


4 


6 


49 


30 


17 


10 


2 


4 


3 


2 


3 


2 


8 


7 


58 


June 1 


4 

10 


1 

1 


i 


2 

1 


2 


1 
2 






2 
6 


3 

5 


15 


4 


3 




29 


7 


81 


46 


14 


7 


8 


7 


8 


8 


16 


36 


231 


9 


55 


14 


17 


10 


6 


3 


12 


11 


30 


31 


189 


11 


21 


11 


6 


7 


2 


4 


2 


3 


3 


4 


63 


14 


44 


17 


8 


2 


5 


6 


5 


8 


15 


17 


127 


16 


36 


25 


13 


7 


4 


4 


3 


4 


16 


19 


131 


18 


35 


21 


9 


8 


4 


7 


6 


5 


21 


6 


122 


20 


15 


6 


7 


2 


2 


1 


4 


1 


8 


8 


54 


22 


8 
16 


2 
7 


3 
2 


1 
4 


2 
2 


2 
3 






8 
8 


8 
3 


34 


24 


2 


2 


49 


27 


16 


5 


5 


4 


2 


3 


3 


3 


2 


8 


51 


29 


6 
4 


7 
3 


3 

2 


1 
1 


3 
1 






1 
1 


2 


8 

1 


29 


July 2 




2 


17 


5 


13 


3 


2 


2 




1 




1 




2 


24 


8 


6 


4 








1 




1 




4 


16 


11 


4 


3 


i 


4 


2 




3 


1 




5 


23 


25 


13 

12 

10 

1 

5 

1 

5 

3 

13 

6 

2 

65 


5 
6 
2 
3 
2 
1 
2 
2 
4 
3 
3 
10 


3 
5 
1 

2 
2 

1 

i 

5 
'5 


3 
3 
1 


2 






1 


3 

2 
5 


4 
1 
3 
2 
1 

2 
1 
2 
6 
1 
25 


34 


29 






29 


Aug. 2 


1 






1 


24 


5 






8 


8 














10 


12 


1 
1 


1 








1 


6 


15 








10 


19 












7 


22 






1 






3 
6 
1 

2 


28 


26 










26 


29 












7 
119 


Sept. 2 


4 


8 


1 


1 


3 




5 


36 


13 


8 


3 


1 


2 


2 




5 


8 


78 


10..... 


7 
32 


1 
3 


3 
4 




1 

4 


1 


2 

1 






4 
9 


18 


12..... 


1 


2 


57 


16 


14 


4 


2 




1 






1 




2 


24 



124 



THE PLUM CURCULIO. 



Table LXXI. — Jarring record for the plum curculio on peach, Barnesville, Ga., 

1910— Continued. 



Dates of 


Number of curculios caught, by rows. 


Total. 


jarring. 


Row 1. 


Row 2. 


Row 3. 


Row 4. 


Row 5. 


Row 6. 


Row 7. 


Row 8. 


Row 9. 


Row 10. 


Sept. 23 

27 


1G 
3 
8 
1 
3 

13 


5 
3 

2 
1 
2 


4 
1 
1 


1 


2 








1 


3 
2 
1 

i 

2 


32 








9 


30 


1 












11 


Oct. 4 










i 


4 


7 














5 


11 


1 




2 








l 


21 


15... 










18... 
























22 
















































Total. 


3,197 


975 


041 


393 


269 


229 


275 


227 


503 


788 


7,497 



A study of this table shows the beetles to have first become active 
March 10, when 16 were taken on row No. 1. During the interim 
March 18 to 23 they began to appear in numbers, and were out in 
full force during the last week of March. Considering the results of 
jarrings from the individual rows, the influence of the woods as 
hibernation quarters is very plainly shown. Thus, up to March 23 
rows Nos. 1 and 2 gave a total of 476 beetles, as against 61 from the 
other eight rows. By March 25, 15 days after emergence began, 
diffusion of the beetles had become quite general over the block, 
though the number taken from the first row on a given date was in 
most cases in excess of that taken from any other single row. For 
the season, row No. 1 yielded 3,197 beetles, 42.64 per cent of the whole 
number captured. From the first three rows adjacent to the woods 
a total of 4,813 individuals was taken during the season, or 64.19 
per cent of the total. The influence of the grass-covered terrace 
between rows Nos. 9 and 10 is also evident, more insects being captured 
from each of these than from any one of the rows Nos. 4 to 8. The 
beetles were in maximum abundance in the orchard from about 
March 25 to April 13, during which period 4,108 individuals were 
taken, or 54.79 per cent of the total. 

The appearance of the new generation of beetles is marked by a 
sudden increase in the jarrings for June 7 and several days subse- 
quently. Beginning with the third week in August an increase in 
the number of beetles taken is again noted, reaching its maximum 
about September 2. This may doubtless be attributed to the issuing 
of the beetles that developed from ripening fruit, the ripening period 
being approximately July 7-20. 

No beetles were captured in this orchard after October 11, though 
the jarrings were continued to October 26. But during late fall 
jarrings were made in other orchards, both sprayed and unsprayed, 
and also in woods adjoining peach orchards. After beetles ceased to 
appear on the regular jarred plats, many were taken in some of these 



NUMBER OF GENERATIONS ANNUALLY. 125 

other places. On October 12, 3 beetles were jarred from 60 trees in a 
sprayed orchard, and 1 beetle from 50 oak and hickory trees in 
adjoining woods. On October 14, 133 beetles were jarred from 104 
trees in a badly infested unsprayed orchard consisting of late varieties. 
The trees in this orchard had been bare of foliage for more than two 
weeks. On the same morning 144 beetles were jarred from 28 small 
oak trees in woods adjoining this orchard, showing a heavy migration 
to the woods. The same 104 peach trees were again jarred October 23. 
Only 30 beetles were taken, and only 7 beetles from 20 oak trees in the 
adjoining woods. On October 26 as many trees as possible were jarred 
in the woods adjacent to the regular jarred block of peach trees. 
Only 3 beetles were secured The last beetles of the season were 
jarred November 1, when 2 beetles were taken from the 104 trees in 
the unsprayed orchard previously mentioned. No beetles were 
secured in jarring 18 oak trees in the adjoining woods on the same date. 
This probably marks the complete entrance of the insect into hiber- 
nation. 

NUMBER OF GENERATIONS ANNUALLY. 

It has been accepted for years that there is but one generation of 
the curculio annually, though this was a much-disputed question 
among the earlier writers. Thus, the writer of an article in the 
National Gazette, which was reprinted in the American Farmer of 
November 15, 1830, states: "There are three generations of them 
during the five months of their existence above ground, and they 
are all very tenacious of life." Dr. Fitch x believed the insect to be 
two-brooded each year, the second brood passing the winter in the larval 
condition under the bark of pear trees. He was led to this erroneous 
belief by the resemblance to the curculio crescent of a curved incision 
in the bark which he supposed was the egg puncture of the insect in 
question. The absence of fruit he thought necessitated this change 
in egg laying by this brood, and agreed with the earlier observations 
of Melsheimer that the curculio bred in the bark of peach trees. 
Dr. Trimble, as the result of observations, believed the curculio to be 
single-brooded, and this opinion was, in the main, accepted by subse- 
quent writers. Dr. Riley, however, in an anonymous communication 
under the signature of "V" in the Prairie Farmer for July, 1867, gave 
it as his conclusions that the insect was occasionally two-brooded. In 
his first Illinois report (1867), Walsh states his belief in the double- 
broodedness of the curculio, as follows: "I find there are two distinct 
broods of the plum curculio every year, the first of which comes out 
in the beetle state, in the latitude of Rock Island, 111., from about 
July 19 to August 4, and the second from about August 23 to Septem- 

i 3d Rept. Ins. N. Y ., p. 351. 



126 THE PLUM CURCULIO. 

ber 28." He cites in detail rearing experiments to support his con- 
clusion, and cites Riley's note in corroboration. 

Riley * fully corroborates the conclusions of Dr. Trimble by rearing 
the curculio in a large cage over a tree, and states emphatically that 
the curculio is single-brooded, but further goes on to say: 

But as there seem to be exceptions to all rules, so there are to this; yet the exceptions 
are only just about sufficient to prove the rule, for as far south as St. Louis not more 
than 1 per cent of the beetles lay any eggs at all until they have lived through one 
winter; or, in other words, where one female will pair and deposit a few eggs the 
same summer she was bred, ninety-nine will live on for nearly 10 months and not 
deposit till the following spring. In more northern latitudes I doubt if any exception 
to the rule will be found. 

During the present study of the curculio but little information on 
the tendency of the insect to produce a second brood under field 
conditions has been secured. Late records of larvae in fruit could 
readily be accounted for as from eggs deposited by the longest-lived 
individuals of the overwintering beetles. 

During 1905, however, at Washington, D. C, a second brood of 
larvae was obtained, though no individuals reached the adult condi- 
tion. Infested peaches were received May 1 from Fort Valley, Ga., 
and confined over moist soil in a large covered glass jar kept in the 
insectary, where temperature conditions were abnormally high. By 
June 8 many adults were emerging from the soil, and on June 12 
several apples were added. On July 13 eggs were found in four 
apples, and subsequently fertile eggs were laid on the 17th, 20th, 21st, 
22d, and 24th of July, and by August 2 several larvae had developed 
to full size, some remaining in the fruit and others entering the soil. 
Several larvae were separated for particular observation, but all of 
these died without transforming to the pupal stage, and no adults 
were secured from larvae entering soil in the breeding jar. 

During the summer of 1910 a second generation was again reared 
under laboratory conditions, at Barnesville, Ga., this time a large 
number of individuals being reared to the adult stage. Adults of the 
first generation were reared out of doors from infested peaches gath- 
ered in an orchard, the beetles beginning to emerge June 6. On 
emerging, the beetles were put in large muslin-covered battery jars, 
100 to 175 beetles to each jar, and kept in the laboratory. They 
were fed on peach foliage and fruit, but were often neglected, allowing 
the jars to become very humid and sometimes moldy. On July 11 
several eggs were found in peaches taken from these jars. The 
beetles, 480 in number, were then supplied with ripe Elberta peaches 
from which all curculio eggs had been removed. On examining this 
fruit two days later 113 eggs were found. Eggs were subsequently 
obtained in abundance, a typical record of eggs laid in fruit left in 
the jars overnight being shown in Table LXXII. 

1 Third Missouri Rept., p. 11. 



BEETLES FROM EMERGENCE TO HIBERNATION. 



127 



Table LXXII. — Record of eggs laid by 864 new-generation beetles during one night, 

Barnesville, Ga., 1910. 



Dates of observation. 


Beetles 
in jars. 


Dates beetles emerged from soil. 


Eggs laid. 


Night of July 26 


120 
113 
156 
185 
109 
101 
80 


June 17 


6 


Do 


June 18-19 


11 


Do. 


June 20-22 


16 


Do 


June 23-25 


49 


Do 


June 26-29 


20 


Do 


June 30-July 4 


27 


Do 


July 5-16 


13 








Total 


864 


142 









The beetles continued to oviposit freely until August 10. By this 
time peaches were scarce and no further observations were made 
until August 17, the beetles being fed on foliage alone during the 
intervening week. On August 17 some late seedling peaches, both 
green and ripe, were put in the jars and on the next day were exam- 
ined for eggs, only two being found. No more eggs could be obtained 
from these beetles or from beetles recently captured by jarring, 
although eggs were being laid in the field, where fruit was available, 
for a month longer. 

All eggs laid by the new-generation beetles appeared to be fertile 
and hatched in from three and one-half to four and one-half days 
unless injured by handling. One hundred and eighty-five individuals 
were reared through to the adult state under the same outdoor 
conditions used in the other rearings. The larvae developed in ripe 
peaches, remaining in the fruit from 9 to 24 days. The life in the 
soil ranged from 18 to 45 days and the entire life cycle from 36 to 
61 days. The adults from this material emerged from the soil August 
22 to October 10. Adults from infested peaches collected in the field 
emerged as late as November 9, at which date there were yet many 
pupae and even larvae in the soil, though there is no evidence that 
these late individuals from the field were of the second generation. 

BEETLES FROM EMERGENCE TO HIBERNATION. 

In general, after emergence the adult insects pass the time in 
hiding and feeding, their activities growing less and less at the 
approach of cold weather, until finally they seek hibernation quarters 
for the winter, which, as shown, may be in orchards under trash, etc., 
on the ground, but especially in neighboring woods. 

More detailed information is needed upon the habits of the beetles 
after emergence, especially in the South and in other regions where 
the fruit crops are practically all gathered by midsummer or earlier. 
Under such conditions the weevils are at once largely deprived of 
fruit for food and doubtless subsist on foliage, buds, etc. In regions, 
as the Middle and Northern States, where a variety of later maturing 



128 THE PLUM CUECULIO. 

fruits is grown, as apples, pears, late peaches, plums, etc., this exi- 
gency in the life of the insect does not occur. Nevertheless, the weevil 
in the Southern States is able to maintain itself in extended areas 
largely devoted to peach growing, as shown by the fact that the 
insect is here perhaps most abundant and destructive. 

The jarring records presented on page 120 show the beetles to be 
present in peach orchards until quite late in the season, but not in 
such numbers as during spring and early summer, indicating a con- 
siderable diffusion or early seeking of hibernation quarters. During 
September, 1905, Mr. Beattie, at Fort Valley, Ga., jarred 400 peach 
trees, securing 600 beetles, which he states were very active and 
were captured on the sheets with difficulty. 

Beetles kept in confinement from time of emergence until hiberna- 
tion have fed freely on fruit when present or on foliage when supplied 
with this alone. Their forced feeding on foliage, as in the South, 
suggests the possibility of destroying them in large numbers by 
thorough spraying with arsenicals after the fruit has been har- 
vested, insuring their material reduction another season. 

In the more northern States the beetles feed freely on various 
fruits but are especially destructive to the apple. The so-called fall 
feeding puncture, in fact, constitutes an important injury to apples, 
pears, plums, etc. The puncture differs somewhat from that made 
in the spring by the overwintering generation. The cavity is cylin- 
drical, as in the case of the spring puncture, but somewhat deeper, 
and is usually excavated beneath the skin all around, as far as the 
length of the snout of the beetle will permit. The opening through 
the skin, about one-sixteenth of an inch in diameter, is surrounded 
with a darkened circle, due to the cavity beneath, which, if the skin 
be removed, will be found to be from one-eighth to one-fourth inch 
across, A single cavity is rarely more than one-eighth inch deep, 
but where the insects are numerous and the fruit scarce the feeding 
punctures may be so abundant as to run together, with the result 
that the injured area of the apple, due to the evaporation through 
the broken skin, collapses, quite destroying the fruit for market 
purposes. (See PL XIII.) Wasps and other agencies, following the 
curculio, may further excavate these feeding punctures, which may 
be invaded by rot-producing fungi and bacteria, soon bringing 
about the decay of the fruit. Often the punctures become so 
enlarged that the beetles are able to get inside, where they feed and 
rest, perhaps spending days there at a time. This character of 
injury was noted years ago by Prof. Comstock. 1 

The extent to which the beetles feed in the late summer was 
determined by Crandall for 10 individuals, separately confined, and 
furnished fresh food, 5 of them daily, the balance about once each 

»Bul. 3, Cornell Univ. Agr. Exp. Sta., p. 40 (1888). 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate XIII 




Fig. 1.— Characteristic Holes Eaten Into Apple by the Beetles in the Fall. 

(Original.) 




Fig. 2.— Feeding Punctures of Beetles on Summer Apples. (Original.) 
THE FALL FEEDING PUNCTURE OF THE PLUM CURCULIO ON APPLE. 



HIBERNATION". 129 

week. A total of 529 punctures was made, or an average of 52.9 
per individual, the range being from 8 to 111 punctures. Examina- 
tions as to curculio injury during the fall of many thousands of 
fruits, as apples, European plums, pears, etc., have always shown 
the feeding punctures of the new generation of beetles, and unques- 
tionably the latter feed freely after emergence and until hibernation. 

HIBERNATION. 

The curculio passes the winter in the adult or beetle stage in trash 
in and about orchards, along fences, and in adjacent woods, etc. 
This fact in the life of the insect has been fairly well understood for 
many years. 

Dr. Tilton, in his article in Willich's Domestic Encyclopedia, in 
1804, expressed the belief that the curculio, like other beetles, 
remains in the form of a grub (or worm) during the winter, ready to 
be metamorphosed to a bug (or beetle) as the spring advanced. 

Dr. Harris, 1 in describing the life history of the insect, as a result 
of his observations, says: 

Meanwhile the grub comes to its growth, and immediately after the fruit falls bur- 
ows into the ground. This may occur at various times between the middle of June 
and of August, and in the space of a little more than three weeks afterwards the insect 
completes its transformations and comes out of the ground in the beetle form. 

He further adds that he has not yet been able to confirm Dr. Tilton's 
observations, but believes that some grubs may be retarded in their 
transformations, thus passing the winter. 

Dr. Fitch 2 states: 

Notwithstanding the volumes that have been written upon it, we do not to this day 
know where the curculio lives and what it is doing three-quarters of the year. 

Dr. Trimble (loc. cit., p. 99) writes: 

Many believe that the curculio lives through the winter in the immature condition 
of a grub and undergoes its transformations in the spring. This is not so. In all my 
numerous experiments made year after year, even with the latest-stung apples, the 
grubs become beetles the same season, and as beetles they live somewhere through 
the winter. 

Further, he details the keeping of beetles in flowerpots covered 
with cheesecloth until quite torpid from the cool weather. Speci- 
mens of beetles were found by Dr. Trimble hibernating under the 
shingles of a roof and in the crevices of a stone wall. 

As stated by Walsh, specimens of beetles were found by a Mr. 
Rathvon under bark of cherry and wild cherry in March and Novem- 
ber. Walsh 3 states: 

There is little doubt now in my mind that the curculios bred from the fruit of one 
year are the same individuals that puncture the fruit of the following year. 

i Nat. Hist. Mass., p. 67 (1841). 3 Practical Entomologist, p. 77 (1867). 

2 Two Addresses, Insects and Curculio (1860). 

17262°— Bull. 103—12—9 



130 THE PLUM CURCULIO. 

But later he complicates the subject by his conclusion that the 
curculio is double-brooded, and that it is the beetles of this second 
brood that survive the winter. On this point of hibernation Riley, 1 
in a summary statement concerning the knowledge of the insect at 
that time, states — 

That the greater portion of them pass the winter in the perfect beetle stage under 
the old bark of both forest and shade trees, under shingles and logs, rubbish of all 
kinds, and especially the underbrush of the woods. 

That a certain proportion of them also pass the winter underground, both in the 
larval and pupal stages, at a depth frequently of from 2 to 3 feet. 

That those which hibernate as beetles begin to leave' their winter quarters and 
enter our orchards throughout central Missouri during the first days of May, and com- 
mence to puncture the fruit about the middle of the same month — a little earlier or 
later, according to the season — the fruit of the peach being at the time about the size 
of a small marble. 

However, Riley, in his Third Report (p. 13), expresses a different 
opinion, and says that he has satisfied himself that the curculio 
invariably passes the winter as a beetle under shelter of all sorts 
near the surface of the ground. This conclusion seems to have been 
adopted by nearly all subsequent writers. There has been, how- 
ever, little exact information on the places where the curculio hiber- 
nates, and indeed little direct effort has been made to find them in 
hibernation. 

Prof. Crandall (loc. cit., p. 495) reports results of searches for 
beetles in Illinois in the spring of 1903. On March 31a whole day's 
search revealed none. Search was made again on April 14, and at 
intervals up to April 27, when first beetles were found under dead 
grass on the ground and occurring singly. Examinations of the 
trees in spring did not reveal the beetles until May 10, when they 
appeared to come all at once, none having been found on the day 
previous. Further search of hibernation quarters, in 1904, was 
made by Prof. Crandall, but no beetles could be found. 

The hibernation habits of the curculio have been investigated at 
various times during the course of the present study of the insect. 
At Youngstown, N. Y., in 1905, Mr. Johnson made frequent searches 
in the fall during October, and on the 14th of that month 9 
beetles were discovered in a slight depression under an apple tree. 
They were well covered with closely matted, well-decayed leaves 
within a space about 2 inches square. Nine more beetles were 
found in a similar situation in an apple orchard on the 16th. On 
October 25 an examination of an uncultivated orchard in light soil 
revealed none, but in an adjoining orchard where there was a sparse 
covering of sod and leaves on the ground, 6 beetles were taken, 4 
being quite dormant and 2 capable of moving feebly. A search on 
November 4 among leaves on the ground in. an apple orchard failed 

i First Missouri Report, p. 53 (1869). 



HIBERNATION. 131 

to reveal any beetles, but, on November 7, 6 more specimens were 
taken beneath partly rotted leaves close to the soil. The beetles 
were wet and dull colored from their surroundings. On November 
17, 2 adults were found, under rotted apple leaves on soil, quite active; 
and in a similar situation 4 more were taken November 23, and 5 on 
November 28. In the spring of 1905 Mr. Johnson made extended 
searches for beetles along fence rows, in peach, plum, apple, and 
quince orchards, in old stumps in adjoining woods,, in cracks in 
fences, under piles of wood, rough bark of fruit and other trees, and 
wherever it was thought possible that the beetles might occur. 
None, however, was discovered. Examinations were made begin- 
ning March 25 and continued until May 10, at which time plum trees 
were showing first blossoms. 

The following year, 1906, at North East, Pa., Mr. Johnson found, 
on April 24, 10 beetles covered with leaves and decayed fruit on the 
surface of the ground in a young apple orchard in sod. At this time 
the blossom buds of apple were just beginning to open. Beetles 
were found in similar situations in this orchard, as follows : Seven on 
April 25, 9 on April 26, 4 on April 30, 16 on May 3. By this time, 
however, beetles were in evidence on certain fruits, as shown by 
Table LXIX, and it is not certain but that some of the beetles 
observed had already left their hibernation quarters for the orchards. 

Also, in the spring of 1905, Mr. James H. Beattie, at Fort Valley, 
Ga., made frequent searches for hibernating curculios, the work cov- 
ering the period from March 14 to 25. Examinations were made 
among leaves and logs in woods, trash in orchards, and other places 
where the insect might occur, but none was found, though unques- 
tionably they were quite abundant in these places. 

The following year at Myrtle, Ga., Messrs. Girault and Rosenfeld 
failed utterly to find any hibernating curculios, although very care- 
ful search was made in all situations likely to be used, including trash 
and grass along terraces, in peach orchards, in thickets of wild plum 
trees adjacent to peach orchards, in accumulations of leaves and 
trash, in old stumps, under rough bark of trees, etc. One beetle, 
however, was found March 16 under the bark of a pear tree about 4 
feet from the ground under circumstances suggesting that it had 
hibernated there. There is doubt in regard to the matter, since the 
trees at this time were in full bloom and the insect may have come 
into the orchard from its hibernating quarters. 

In the case of apple orchards the data show that many beetles 
simply hide away under trash that may be present. They doubtless 
feed upon the fruit until fall, and upon the coming of cold weather 
seek the most convenient shelter. In the case of fruits gathered by 
midsummer, as is true of peaches in the South and in regions where 
other fruits are not available for food, unquestionably the insects 



132 THE PLUM CUECTJLIO. 

become very much scattered, and there are no data to show just 
where they hibernate, though it has long been known that beetles 
are first in evidence in those portions of orchards adjacent to woods. 
(See tables of jarring records, pp. 120-125.) Unquestionably the 
bulk of them hibernate in trash in woods adjacent to orchards, and 
also in grass along terraces in. orchards, and probably to a less extent 
in orchards. 

Some data were obtained also by Mr. Johnson at Youngstown, 
N. Y., in the fall of 1905, upon the actions of the beetles in seeking pro- 
tection. On September 28, 6 curculios were placed on bare loose soil 
and covered with large glass jars. After several days of cold weather, 
including a couple of hard freezes, the beetles were found on October 
20 on the surface of the soil and in a perfectly quiescent condition. 
Later, November 13, there had been no change in the condition of 
the beetles. Specimens collected early in September, feeding upon 
apples and confined in jars, in which was a supply of turf, made no 
attempt to burrow into the sod. As the weather became colder they 
mostly fell from the apples, inclosed for food, lying promiscuously 
among the blades of grass at the base of the fruit. Beetles were still 
hiding in cavities previously eaten in the apples. On November 22, 
however, alter some activity, due to a few days of warm weather, 
several beetles had crawled nearly out of sight in the sod and several 
more had worked down into cracks between the pieces of sod, indi- 
cating a distinct tendency to seek shelter. 

MORTALITY OF THE CURCULIO DURING HIBERNATION. 

The proportion of beetles which survive the winter doubtless 
varies considerably from year to year, depending upon the character 
of the weather and other conditions. Observations on this point, 
however, indicate a heavy mortality. September 4, 1905, 400 
beetles jarred from peach trees at Fort Valley, Ga., were placed in 
breeding cages in the insectary yard at Washington and supplied 
with fruit for feeding purposes and abundant dried leaves and trash 
under which to protect themselves during the winter. Examinations 
made October 12 and 28 indicate that they were doing well and had 
fed more or less upon the fruit present. At these dates most of the 
beetles were hiding under the trash at the bottom of the cage. A 
preliminary examination, March 2, 1906, showed that many of the 
beetles had become active, some of them crawling rapidly here and 
there in the cage. On April 6 a final examination was made, especial 
care being taken to miss none of the insects. The leaves and sand 
were carefully worked over, and 60 live beetles were found and 138 
dead ones. Thus a total of 198 individuals were accounted for out 
of 400 originally placed in the cage. Doubtless the missing ones had 



MORTALITY DURING HIBERNATION. 



133 



died and decomposed and thus escaped notice. Their escape from 
the cage was scarcely possible, as this was kept tightly closed all the 
while. A similar experiment was made at Siloam Springs, Ark., in 
the fall of 1908. October 9, 1,280 beetles reared from peaches were 
distributed in four battery jars and kept out of doors under shelter. 
An examination on November 2 showed that 965 beetles were alive 
and 308 dead, with 7 unaccounted for. These 965 beetles were then 
placed in a cage in a moderately exposed place out of doors and 
covered to protect from beating rains. The cages were supplied 
with a quantity of small chips, dried leaves, paper, and muslin. The 
insects passed the winter in this condition, but unfortunately the 
cage met with an accident in the spring and final results were not 
obtained. In the course of rearing work at Barnesville, Ga., during 
1910 many beetles were obtained, some of which were used to obtain 
data on their mortality before hibernation in the fall and during the 
winter. As shown in Table LXXIII, 10 different lots of beetles were 
thus carried through the fall and winter in boxes covered with wire 
screen, the total number of individuals under observation being 2,378. 
Up to November 4, 1910, the time of final examination in the fall, a 
total of 487 beetles had died, with 112 unaccounted for and listed as 
escaped. A total of 1,779 beetles were placed in cages as shown for 
the winter. At date of final examination in the spring, March 8,. 191 1, 
648 five beetles were found, with 619 dead and 512 missing; the last 
probably decomposed. The average percentage alive is seen to be 
36.42. The percentage of mortality of the different lots does not 
seem to give consistent evidence as to hibernation material and 
exposure best suited to them, as will be noted from the table: 

Table LXXIII. — Mortality of hibernating beetles of the plum curculio, Barnesville, 

Ga., 1910-11. 



Lot No. 


Period of emer- 
gence. 


Emerged. 


Food. 


Lost wh ; le feed- 
ing up to Nov. 4, 
1910. 


Total 
put m 
winter 




Died. 


Escaped. 


cage. 




1910. 

Sept. 16-30 

June 13-22 

Oct. 1-Nov. 3 

Aug.6-Sept 6 . 
June 30-July 16... 

Sept. 7-9 


13S 
573 

101 
311 
1S1 

216 
294 

127 

1317 

120 


Peach foliage and apples 

Peach foliage, peaches, and 
apples. 


4 
294 

2 

72 
3S 

6 
38 

6 
14 
13 




134 


2 


hi 


222 




99 




Peach foliage only 


9 

18 

4 
9 

o 
1 
12 


230 


5 


Peach foliage, peaches, and 

apples. 
Peach foliage only 


125 


6 


206 


7 


June 23-29 

Sept. 10-15 

Oct. U-22i 


Peach foliage, peaches, and 
apples. 

Peach foliage and apples 

do 


247 


8..- 


119 




302 


10 


Peach foliage only after Aug. 30. 


95 










2,378 


4S7 


112 


1,779 











i Jarred. 



134 



THE PLUM CURCULIO. 



Table LXXIII. — Mortality of hibernating beetles of the plum curculio, Barnesville, 

Ga., 1910-11— Continued. 



Lot No. 



Total. 



Date 
put in 
winter 

cage. 



1910. 

Nov. '. 
...do... 

..do... 
...do... 

..do... 
...do... 
...do... 
...do... 
...do... 
...do... 



Hibernation material used and 
exposure. 



Chips; exposed to rain 

Sod; exposed to rain 

Dry leaves; exposed to rain 

Dry leaves; sheltered 

Hay; exposed to rain'. 

Dry leaves; exposed to rain 

Bare dirt; exposed to rain 

Chips; sheltered 

Dry leaves; exposed to rain 

Dry oak leaves; exposed to rain. 



Date 

final 

exami- 

tion. 



1911. 

Mar. 8 

..do.. 

..do.. 

..do.. 

..do.. 

..do.. 

..do.. 

..do.. 

..do.. 

..do.. 



Alive. 



79 
in.] 

04 

53 
113 
111 

86 
1 



Dead. 



16 

60 

24 

133 

3 

59 

94 

100 

127 

3 



619 



Miss- 
ing. 



39 
58 
11 
44 
9 
36 
67 
18 
173 
57 



Per- 
centage 
alive. 



58.95 
46.84 
64.64 
23.04 
90.40 
53.88 
34.81 
.84 
.66 
36.84 



3?. 42 



i Based on totals. 



Observations on the hibernation of beetles were also made by Mr. 
Hammar during 1910 at Douglas, Mich. To determine if any indi- 
viduals lived over two seasons, a lot of beetles, 1,591 in number, 
were placed in rearing j ars as collected from the trees between May 7 
and June 30, and before any beetles of the new generation had 
appeared. These were supplied with food during the summer and 
fall until hibernation. On May 10, 1911, the contents of the cages 
were examined and the sand sifted, and 1,400 individuals recovered. 
No live beetles, however, were found, though some were alive in the 
fall. This indicates that the beetles do not live over a second winter. 

A lot of beetles, 610, reared from fruit in the laboratory during the 
summer of 1910 was placed in a rearing cage in a protected place out 
of doors and fed until hibernation. At the final examination, May 
10, 1911, 416 dead beetles were found and the remains of a few dis- 
integrated individuals. The live beetles unfortunately had escaped 
through an imperfection which developed over winter in the cage. 
These figures, however, give a winter mortality of about 70 per cent. 

PERCENTAGE OF FRUIT PUNCTURED OR INFESTED BY THE 

PLUM CURCULIO. 

In a general way it has long been known that the curculio, through- 
out its area of distribution, injures or destroys a large amount of 
fruit each year. The amount of injury will vary from season to 
season, and will depend more particularly upon local conditions in the 
orchard. Injury will be notably worse in uncultivated orchards and 
where good hibernation quarters are afforded the beetles. Cultivated 
and sprayed orchards suffer least, though in well-cultivated, southern 
peach orchards the pest is often quite destructive. In connection 
with spraying experiments during the past several years, the per- 
centage of fruit injured by the curculio on untreated trees has been 



FRUIT PUNCTURED OR INFESTED. 



135 



determined for various fruits and localities by actual counts of fruit. 
Typical data of this kind are furnished in the tables following. Not 
all fruit punctured is worthless, though its market value is reduced. 

In Table LXXIV are given data on amount of fruit infested by 
larvae from specified trees in several localities in Georgia and in Penn- 
sylvania, including both drop and picked fruit. On account of the 
difficulty of determining punctures in the peach, only actual infesta- 
tion was noted, mostly of fallen fruit. 

Table LXXIV. — Percentage of infested -peaches for the season, various localities. 



Mayfleld, Ga 

Marshallville, Ga. 

Myrtle, Ga 

Arlington, Va 

North East, Pa.. 
Do 



Total and average per 
cent of injury 



Season. 



1907 
1908 
1906 
1906 
1906 
1906 



Variety. 



Elberta 

Red River 

Belle of Geoxgia. 
Miscellaneous . . . 

Sneed 

Hills Chili 



Trees 
used. 



Fruit from ground. 



In- 
fested. 



328 
167 
231 
593 
2,522 
831 



4,672 



Sound. 



229 
467 
238 
1,495 
941 
171 



3,541 



Total. 



557 

634 

469 

2,088 

3,463 

1,002 



8,213 



Localities. 



Variety. 



Trees 

Used. 



Fruit from trees. 



In- 
fested. 



Total. 



Total 
. in- 
fested. 



Total 
sound. 



Per- 
centage 
infested 

for 
season. 



Mayfleld, Ga 

Marshallville, Ga... 

Myrtle, Ga 

Arlington, Va 

North East, Pa 

Do 



1907 
1908 
1906 
1906 
1906 
1906 



Elberta 

Red River 

Belle of Georgia. 
Miscellaneous. . . 

Sneed 

Hills Chili 



518 
100 
264 
35 





113 

2,264 

895 

489 

2,200 



631 

2,364 

1,159 

524 

2,200 



846 
267 
495 
628 
2,522 
831 



342 
2,731 
1,133 
1,984 
3,141 
1,019 



71.21 
8.91 
30.40 
24.04 
44.53 
44.91 



Total and av- 
erage per 
cent of in- 



jury- 



6,809 



7, 726 



5,589 



10, 350 



As shown in Table LXXIV, the percentage of infestation to peaches 
in the several localities varies from 8.91 to 71.21 per cent of the total 
crop produced, with an average of 35.06. These figures represent the 
actual proportion of the crop destroyed, since it includes only infested 
fruit. The total number of infested fruits from the ground, 4,672, 
exceeds notably that infested on the trees, i. e., 917. The percentage 
of drop fruit infested is 56.87, as compared with 11.86 per cent from 
the trees at picking time. During seasons of light crops practically 
all of the fruit may become infested when small and drop, though 
during years of full crops the thinning out by the beetles is not 
especially important. 

In Table LXXV is shown the condition of the drop fruit for the 
season from 120 Elberta peach trees at Siloam Springs, Ark., during 
1908. The fruit at picking time was by mistake of orchardist 



136 



THE PLUM CURCULIO. 



removed before records could be made of condition of same. The 
percentage of infestation, 11.25, is notably less for drop fruit than 
shown in the preceding table, 56.87, due to the greater scarcity of the 
beetles. 

Table LXXV. — Percentage of injury to drop peaches, Siloam Springs, Ark., 1908. 



, Dates fruit was collected. 


Fruits. 


Fruits 
infested. 


Apr 30 


2,500 

6,500 

30, 840 

7,200 

2,400 

498 

198 

135 

251 

68 

101 

21 

16 

41 

90 

104 

689 

648 

328 


1 481 


May 9 


674 


16-19 


1,658 


21 


958 


25 


301 


30 


89 




80 


8 : 


56 


13 


67 


17 


19 


22 


25 


27 


7 


July 1 


2 


5 


15 


11 


50 


15 


30 


20 


300 


25 


87 


29 


21 








Total 


52, 628 


5,920 







Average per cent of infestation, 11.25. 

The degree of infestation by the curculio of all fallen fruit for the 
season from 10 peach trees in the District of Columbia is shown in 
Table LXXVI. The percentage of infestation, 44.73, closely 
approximates the averages of the figures in Table LXXIV. 

Table LXXVI. — Percentage of injury to drop peaches, Washington, D. C, 1908. 



Dates fruit was collected. 


Number 

of 

fruits. 


Number 
of fruits 
infested. 


May 24 


676 

2,500 

902 

247 

79 


342 




1,202 


10 . 


290 


16. . 


124 


July 3 . - 


12 








Total 


4,404 


1,970 







Average per cent of infestation, 44.73. 



FRUIT PUNCTURED OR INFESTED. 



137 



Extent of injury to miscellaneous sorts of plums is indicated in 
Table LXXVII. Kecords were made by gathering the specified 
number of fruits here and there from the trees or from the ground. 
It is regretted that similar data are not available from more northern 
localities. 

Table LXXVII. —Percentage of injury to plums by egg and feeding punctures, various 

localities. 



Localities. 


Varieties. 


Date col- 
lected. 


Fruits 
with egg 
punc- 
tures. 


Fruits 
with 
feeding 
punc- 
tures. 


Unin- 
jured 
fruit. 


Total 
num- 
ber of 
fruit. 


Average 
percent- 
age of 
fruit 
injured. 


Remarks. 


Myrtle, Ga 
Do 


Wild plum.. 
do 


1908. 

Apr. 9 

13 

20 

22 

30 

30 

May 8 

8 

31 

31 

June 6 

6 

11 

Apr. 9 

14 

May 7 

7 

1905. 
May 9 
9 
26 
26 
22 
22 


22 
37 
43 
36 
36 
43 
36 
32 
22 
34 
27 
40 
28 

4 
61 

3 
32 

33 
63 
117 
122 
30 
35 


14 
14 
• 6 
10 
5 
4 
4 
5 
5 
4 
3 
8 
2 
6 
13 
5 
3 

12 

25 

4 


164 

49 

51 

4 

9 

3 

10 

13 

23 

12 

20 

2 

20 

90 

26 

17 

55 

112 

18 

2 
61 

5 


200 
100 
100 
50 
50 
50 
50 
50 
50 
50 
50 
50 
50 
100 
100 
25 
35 

100 
200 
139 
124 
100 
50 




From trees. 




Do. 


Do 


...do 




Do. 


Do 


...do 




From ground. 


Do 


...do 




From trees. 


Do 


...do 




'From ground. 


Do 


...do 




From tree. 


Do 


...do...... 




From ground. 


Do 


.. do 




From tree. 


Do 


do 




From ground. 


Do . 


...do 


From tree. 


Do 


...do 




From ground. 


Do : . 


do 




From tree. 


Do . 


Red June . . . 
...do 




Do. 


Do 




Do. 


Do... 


do 




Do. 


Do .. 


do 




From ground. 




Burbank 

do 




From tree. 


Do 




Do. 




(?) 
(?) 
(?) 
(?) 




Do. 


Do 




From ground. 


Bennines, D. C. 
Do .". 


9 

10 




From tree! 




From ground. 








Total for all 


936 


171 


766 


1. 873 


59.10 




localities. 









In the above table the figures for injury show merely the number of 
punctures. While most of the fruit punctured would fall, not all of 
it would do so, the fruit more or less outgrowing the injury. The 
average percentage of injury, i. e., 59.10, is therefore perhaps a little 
high. 

The extent to which pears may be punctured is shown for two 
localities in Table LXXVIII. As elsewhere explained, the real injury 
to such pears as Le Conte and Kieffer is small, as the thinning of the 
young fruit is in most cases desirable and the punctures are mostly 
outgrown by the fiuit on the trees. 



138 



THE PLUM CUECULIO. 



Table LXXVIII. — Percentage of injury to pears by egg and feeding punctures, Georgia 

and Maryland. 



Localities. 


Varieties. 


Date col- 
lected. 


Fruits 
with egg 
punc- 
tures. 


Fruits 
with 
feeding 
punc- 
tures. 


Unin- 
jured 
fruit. 


Total 
num- 
ber of 
fruit. 


Average 
percent- 
age of 
fruit 
injured. 


Remarks. 


Myrtle. Ga 

Do 


LeConte 

.do 


190G 
Apr. 9 
9 

14 
14 
20 
20 
May 2 

4 

31 

Apr. 4 

9 

9 
13 
13 
20 
20 
May 2 

4 
31 
12 
12 


11 


7 
12 


182 
188 
93 
86 
35 
44 
2S 
37 
35 
1C0 
173 
152 
59 
84 
23 
34 
29 
25 
28 
25 
42 


200 

200 

100 

100 

50 

50 

50 

50 

50 

200 

200 

1C0 

100 

100 

50 

50 

50 

50 

50 

45 

127 








From ground. 


Do 


.do... 


7 

4 
11 

4 
19 
10 

7 

18 
IS 

3 
29 

9 
25 
13 
16 
18 
10 




From tree. 


Do 


...do 


10 

4 
2 
3 
3 

8 
22 
9 
5 
12 
7 
2 
3 
5 
7 
12 




From ground. 


Do 


...do 




From tree. 


Do 


..do... 




From ground. 


Do 


.do... 




From tree. 


Do 


...do 




From ground. 


Do 


.do 




From tree. 


Do 


Keifler 

.do 




Do. 


Do 




Do. 


Do 


...do 




From ground. 


Do 


...do 




From tree. 


Do 


..do... 




From ground. 


Do . 


do 




From tree. 


Do 


do 




From ground. 


Do 


.do... 




From tree. 


Do 


do... 




From ground. 


Do 


do 




From tree. 




Birtlett 
Keifier 




Do. 


Do 








Do. 














232 


133 


1.5G2 


2. 032 


23.12 




averageper 
cent of in- 
j ury for 
botliloc ..li- 
tics. 









The extent of injury to apples in several localities during 1908 and 
1909 is shown in Table LXXIX. These records are from unsprayed 
or control trees used in spraying experiments and demonstrations 
against the codling moth and plum curculio, and are further referred 
to under the heading of spraying apples (p. 193). 

Table LXXIX. — Number of egg and feeding punctures and percentage of injury to apples, 
including drop fruit and fruit from tree, various localities, for seasons 1908 and 1909. 



Localities. 


Variety. 


Date. 


Tree 

No. 


Egg 

punc- 
tures. 


Feed- 
ing 
punc- 
tures. 


Injured 
fruit. 


Total 
num- 
ber of 
fruit. 


Aver- 
age per- 
centage 
of fruit 
injured. 


Anderson, Mo 

Do 


Lansingburg 

do 


Season 1908. 
Season 1908. 
Season 1908. 
Season 1908. 
Season 1908. 
Season 1908. 
Season 1908. 
Season 190S. 
Season 1908. 


1 
2 
3 
4 
5 
6 
7 
8 
9 


1,486 
1,5C2 
1.492 
1,615 
1,910 
1,882 
2,547 
2,142 
2,021 


438 
542 
381 
448 
539 
573 
907 
599 
752 


166 
298 
219 
284 
389 
344 
544 
• 484 
566 


1C9 
308 
235 
298 
400 
368 
585 
516 
626 




Do 


do 




Do 


do 




Do... 


do 




Do .. 


do 




Do . 


do 




Do 


...do 




Do... 


do 












16, 657 


5,179 


3,294 


3,505 


93.98 


age per cent 
of injury. 


Ben Davis 

.. do 


Season 1908. 
Season 1908. 
Season 1908. 
Season 1908. 
Season 1908. 
Season 1908. 
Season 1908. 


1 
2 
3 
4 
5 
6 
7 




Douglas, Mich 

Do... 


538 
916 
1,241 
1,778 
2,343 
9,482 
4,627 


301 
282 
740 
780 
1,121 
891 
493 


274 

316 

528 

458 

1,012 

1,079 

1,285 


751 

592 

944 

933 

3,003 

1,132 

1,632 




Do 


do : 




Do 


Hubbardstown 

do 




Do 




Do 

Do 


Oldenberg 

do 












20, 925 


4,011 


4,952 


8,987 


55.10 


age per cent 
of injury. 











NATURAL ENEMIES. 



139 



Table LXXIX. — Number of egg and feeding punctures and percentage of injury to 
apples, including drop fruit and fruit from tree, various localities, for seasons 1908 
and 1909 — Continued. 



Localities. 


Variety. 


Date. 


Tree 
No. 


Egg 
punc- 
tures. 


Feed- 
ing 
punc- 
tures. 


Injured 
fruit. 


Total 
num- 
ber of 
fruit. 


Aver- 
age per- 
centage 
of fruit 
injured. 


Westfield, N. Y 




Season 1908. 
Season 1908. 
Season 190S. 
Season 1908. 
Season 1908. 


1 
2 
3 

4 
5 


139 
169 

119 
147 
191 


52 
' 140 
62 
65 
121 


181 
298 
283 
212 
2S0 


748 
1,518 

881 
1,100 

838 




Do 


...do 




Do 


do • 




Do 


.do... 




Do 


...do 












765 


440 


1, 2G0 


5,085 


24.77 


age per cent 
of injury. 


Yellow Newtown. 
do 


Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 


1 
2 
3 

4 
5 
6 
7 
8 




Crozet, Va 


1, 670 
1,027 
479 
631 
1,419 
1,068 
1,433 
1,170 


1,076 
944 
226 
331 

1,071 
871 
865 
695 


1,255 
1,571 
437 
531 
1,415 
1.193 
1, 285 
1,098 


3,423 
3, 6S2 - 
816 
1,016 
3,111 
2,988 
2,091 
1,980 




Do 




Do 


....do 




Do 


....do 




Do 


...do 




Do 


...do 




Do 


...do 




Do 


do 










Total and aver- 


9,497 


6. 079 


8,785 


19, 107 


45.97 


age per cent 
of injury. 




Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 


1 

2 
3 

4 

5 
6 




Fislierville, Va 


1,326 
727 
1,718 
1,573 
2,793 
1,019 


536 
389 
518 
378 
795 
200 


1,350 
799 
1,378 
1,420 
2,307 
803 


4, 463 
3,134 
3,537 
4,055 
5,892 
2,244 




Do 


...do... 




Do 


...do 




Do 


...do... 




Do 


...do... 




Do 


.do... 










Total and aver- 


9,156 


2,822 


8,057 


23, 325 


34.53 


age per cent 
of injury. 


Ben T>avis 

do 


Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 
Season 1909. 


1 
2 
3 

4 
5 
6 

7 
8 




Mount Jackson, Va. . . 
Do 


5,119 
3,545 
1,703 
2,179 
3,723 
4,113 
5,541 
3,785 


2,217 

952 

509 

709 

1,307 

2,009 

3,238 

1,199 


3,186 
2,226 
1,079 
1,226 
2,399 
2,823 
3,611 
2.107 


3,926 
3,109 
1,840 
1,508 
3,189 
4,153 
5,121 
2,795 




Do 


do... 




Da 


...do... 




Do 


do 




Do 


do 




Do 


...do 




Do 


...do 










Total and aver- 


29, 708 


12, 140 


18,657 


25,641 


72.72 


age per cent 
of injury. 











The injury indicated for apples ranges from 93.88 to 24.77 per cent 
of the total crop, both dropped and picked fruit. It is not to be 
inferred that the figures indicate the actual amount of fruit lost 
from curculio attack, since in many instances in the case of fruit from 
trees there would be but a single feeding puncture, or an old egg scar, 
largely outgrown. Such specimens, while unfit for fancy market 
fruit, would possess considerable value. 

NATURAL ENEMIES. 

There are many factors which taken collectively exert an important 
influence on the numbers of the curculio, as unfavorable conditions 
during the winter, drought during pupal period and time of emergence 
of beetles from the soil, scarcity of fruit for oviposition due to frosts 
or other causes, and the influence of parasitic and predaceous enemies 
and disease. Notwithstanding all of these, the insect is able to main- 



140 



THE PLUM CURCULIO. 



tain itself most successfully, and puts in its appearance in the spring 
in numbers with much regularity. Under favorable conditions for 
development, as in neglected orchards, they often become excessively 
abundant, but for any locality do not show as a rule any great varia- 
tion in numbers from season to season. Although the curculio in 
its egg, larval, and pupal stages lives well protected — as in the fruit 
and below the soil— yet it is subject to the attack of several species 
of parasites. 

PARASITIC INSECTS. 

(Anaph.es) Anaphoidea conotracheli Girault. 

Only one parasite of the egg of the curculio is known, namely, 
(Anaphes) Anaphoidea conotracheli Girault, first reared by the senior 

author in 1902 at 
College Park, Md., 
and next from ma- 
terial collected in 
1905 at Fort Valley, 
Ga. (See fig. 25.) 
The description of 
this species by Gir- 
ault will be found 
in Entomological 
News. 1 These mi- 
nute insects, barely 
visible to the naked 
eye, are quite active, 
jumping readily 
when disturbed. 
This parasite ap- 
pears to be widely 
distributed, and has 
been reared from eggs of the plum curculio in the fruits indicated, 
from the following localities: 

Table LXXX. — Records of rearings of (Anaphes) Anaphoidea conotracheli, various 

localities. 




Fig. 25 — (Anaphes) Anaphoidea conotracheli, an egg parasite of the 
plum curculio. (Original.) 



Localities. 


Date. 


Fruit. 


Berlin, Conn 


July 3-18, 1905.... 


Plum. 


Washington, D. C 


May 9-31, 1905 


Plum, apricot. 
Apple. 

Apple, plum. 
Peach, pear, plum. 
Peach, cherry, apple. 
Apple, cherry. 
Apple. 
Plum, 


College Park, Md 


July 22-29, 1905 


Riverdale, Md 


May 3-July 24, 1905. . . 


Arundel, Md 


May 16-June 15, 1905 . . . 


Arlington, Va 


June 13-July 13, 1905 


Alexandria, Va 


June 15-16, 1905.. 


East Falls Church, Va 


Aug. 12, 1905 


Victoria, Tex 


June 15, 1905... 


Tryon, N. C 


May 20, 1905 


Do. 




June 18, 1905 

May 30, 1905 

May 9- June 28, 1905 . 


Do. 


Ardmore, Okla 


Wild plum. 

Wild plum, Japan plum. 

Wild plum. 


Fort Valley, Ga 


Myrtle, Ga 


Apr. 26-May 13, 1900. . 


Charlottesville, Va 


May 18, 1905 


Barnesville, Ga 


May 17-26, 1910 


Wild plum. 







i Ent. News, vol. 16, p. 220 (1905). 



NATURAL ENEMIES: PARASITIC INSECTS. 141 

From the records from localities in the environs of Washington, 
(College Park, Riverdale, Arundel, Md., and Arlington, Alexandria, 
and East Falls Church, Va.) it would appear that the insect is out 
ovipositing nearly coincident with the period of oviposition of its 
host, namely, May 3 (Riverdale, Md.) to August 12 (East Falls Church, 
Va.). Hearings have been made from eggs in various fruits, including 
wild and cultivated plum, and it is probable that the parasite will 
search out eggs in any fruit used by the curculio for egg laying. 

In its distribution the-Anaphoidea is seen to range pretty well over 
the Eastern States, and rearings from Ardmore, Okla., indicate its 
occurrence in the Southwestern States. The insect probably follows 
its host, though no data of note are at hand as to its distribution in the 
Mississippi Valley and Middle-Western States. 

In several instances it was possible to determine the percentage of 
parasitism of the eggs. Thus, in a lot of eggs from Arundel, Md., in 
plums collected from trees May 9, 62.8 per cent yielded adults of the 
Anaphoidea. In another lot from the same locality, on the same 
date and host, the parasitism amounted to 70.76 per cent. A lot 
from Berlin, Conn., in plum, gave about 85 per cent parasitism. 

At Myrtle, Ga., eggs in wild plum collected May 16 gave 10 per cent, 
and another lot taken May 1 gave 16.6 per cent parasitized. From 
Bemiings, D. C, a lot of eggs in plum taken May 31 gave 12.2 per cent 
parasitized. 

Of 36 eggs collected at Barnesville, Ga., May 17, 36.11 per cent 
gave out adult parasites. In a lot of 28 eggs collected May 19 the 
percentage was 46.43, and of 97 eggs collected May 26 the percentage 
producing adult parasites was 56.70. In these three lots, if account be 
taken only of the eggs which either hatched or gave out adult parasites, 
the proportions parasitized would be 46.43 per cent, 76.47 per cent, and 
91.66 per cent. Five eggs in these lots produced two parasites each. 

Certain observations on the habits and biology of the Anaphoidea 
parasites, made by Mr. Girault, are of interest, especially in view of 
the paucity of our knowledge concerning these minute creatures. 
Parasitized eggs were found to maintain their normal pale white 
color until within two days of the emergence of the parasite, at which 
time or a little later the large reddish eyes and the three reddish ocelli 
between them become evident and the general outline of the parasite 
becomes discernible. Gradually the parasite becomes dusky and a 
few hours before emergence almost entirely black. The time required 
for the development of Anaphoidea from egg to adult varied from 
9 to 11 days, averaging approximately 10 days. Thus during the 6 
to 8 weeks of egg laying of the curculio there would be time for six or 
seven generations of the parasite. 

Oviposition was observed several times. In a typical instance, 
the female carefully examined the egg puncture, winch was two days 
old; the long flexible antennae moved alternately up and down very 



142 



THE PLUM CURCULIO. 



rapidly, tapping the plum. After an instant of greater excitement 
she suddenly stopped, with body raised, holding the antennae straight 
and rigid before her. The slender ovipositor was quickly inserted, 
the tip of abdomen being bent cephalad for the purpose. Oviposition 
occurred within 30 seconds. In removing the ovipositor the antennae 
were lowered partly beneath the fore-body, evidently as a help, and 
the abdomen quickly arched. 

(Sigalphus) Triaspis curculionis Fitch. 

The Sigalphus parasite of the curculio (fig. 26) was first discovered 
by Dr. Fitch, and a description with figure of the female published 
in the Country Gentleman for October, 1859 (p. 221), and also in the 
Albany Cultivator in October of the same year. A more extended 
account is given in his address ' ' On the curculio and black knot on 
plum trees," delivered before the New York Agricultural Society in 
1860. The specimens upon which the description was based came 

from D. W. Beadle, St. 
^^^^^ff 6 ^^, / Catherines, Ontario, and 

\N^ ^/y na d been reared by him 

from black knot on plum 
trees which were infested 
with curculio larvae, the 
adult curculios appearing 
in numbers in the rearing 
jars. The fact that the 
black knot is also infested 
by the larvae of other in- 
sects, especially that of 
the so-called plum moth 
(Enarmonia prunivora Walsh), casts doubt on the exact host relations 
of the Sigalphus. In fact, Walsh in his report as acting entomologist 
of Illinois ridiculed the idea that the Sigalphus was a parasite of the 
curculio, and this doubt was hot removed until 1870, when Dr. Riley 
reared the insect in large numbers from curculio larvae placed in jars 
in carefully sifted earth. 

Little has been added to our knowledge of this insect since the 
observations by Riley. Prof. Gillette, in Iowa Station Bulletin 9, 
page 378, gives some interesting notes on the insect; he found it 
quite common in the vicinity of Ames during the summer of 1889. 
The variety rufus Riley, later mentioned, was four times as abundant 
as the true curculionis. The substance of the same article was also 
published in the Canadian Entomologist, volume 22, page 114 (1890). 
The Sigalphus has been reared by Fayville and Parrot, in Kansas, 
from larvae of the potato stalk weevil, Trichobaris trinotata Say 
(Kansas Station Bulletin 82, p. 12), and the parasite is recorded 
from the same host by Dr. Chittenden (Bui. 33, n. s., Bur. Ent., 




Fig. 26. — {Sigalphus) Triaspis curculionis, an important parasite 
of the plum curculio: a, Male; o, female; c, antenna. (After 
Riley.) 



NATURAL, ENEMIES: PARASITIC INSECTS. 



143 



U. S. Dept. Agr., p. 17). The insect was reared from the cotton boll 
weevil (Anthonomus grandis) at Calvert, Tex., and is doubtfully 
recorded from Conotrachelus juglandis Lee. Specimens of curculionis 
were also received from Prof. A. H. Conradi, Clemson College, S. C, 
in 1908, and from Prof. Fred E. Brooks, Morgantown, W. Va., Jan- 
uary, 1907, who had reared them from Balaninus sp. As stated by 
Mr. W. D. Pierce (Journ. Econ. Ent., vol. 1, p. 386), it com- 
monly attacks Conotrachelus elegans Boh., at Dallas and Victoria, 
Tex. At Four Mile Run", Va., it was reared from Trichobaris trinotata 
Say in eggplant. Riley records the Sigalphus from a stalk-borer 
in Ambrosia (Ins. Life, vol. 2, p. 353). In West Virginia it has been 
reared in abundance from Conotrachelus affinis Boh. and in lesser 
numbers from C. juglandis Lee. (W. Va. Agr. Exp. Sta., Bui. 128. 
p. 182). 

This, so far as the writers know, is the complete host list of the 
species, and Sigalphus is so much more common on Conotrachelus 
nenuphar that this is without doubt its principal host. 

(Sigalphus) Triaspis curculionis is of general occurrence througn- 
out eastern North America, its range probably being coextensive 
with that of the plum curculio. A list of localities, with dates, of 
rearing, is given in Table LXXXI. 

Table LXXXI. — Distribution of (Sigalphus) Triaspis curculionis, with dates of 

rearing. 



Localities. 


Dates of emergence. 


Localities. 


Dates of emergence. 


New Haven, Conn 

Youngstown, N. Y 


July 12-18, 1905. 
July 14-Aug. 18, 1905. 
July 8-14, 1906. 
June 24-July 12, 1907. 
July 21, 1905. 
July 18, 1905. 
June 21-July 26, 1905. 
June 16-July 6, 1905. 
May 22-July 17, 1905. 
June 24-July 30, 1908. 
June 2-July 30, 1905. 
June 15-17, 1905. 
June 20, 1905. 
Do. 


Fort Valley, Ga 


May 22-July 3, 1905. 
June 10, 1906. 


North East, Pa 

New Richmond, Ohio.. 


Barnesville, Ga 

Lake City, Fla 


May 23-June 30, 1910. 
May 23, 1905. 
May 31, 1905. 
June 15, 1905. 
June 18, 1905. 


East Lansing, Mich 




Valparaiso, Ind 

Arundel, Md 


Garrison, Tex 


Riverdale, Md 

Washington, D. C 

Do 


Siloam Springs, Ark 

Bentonville, Ark 


June 3-.Tuly 18, 1908. 
June 24-26, 1906. 
June 21-July 8, 1905. 
July 22, 1910. 
July 18-22, 1910. 
Do. 


Arlington, Va 




Winchester, Va 

Raleigh, N. C 

Tryon, N. C 


Grand Island, Nebr 

North Platte, Nebr 



Localities in literature: 

St. Catherines, Ontario (Fitch). 
St. Louis, Mo. (Riley). 
Ames, Iowa (Gillette). 

The insect has been reared from many localities during the past 
four or five years, exclusively from plum curculio larvae, but never 
in noteworthy numbers, although the degree of parasitism in a few 
cases reached 25 per cent. This would vary, perhaps, depending 
upon when the infested fruits were collected, as larvae are parasitized 
principally in early spring. In three records that covered the entire 
season the average infestation was 2.78 per cent. 

In connection with the records of emergence of larvae from fruit 
for the season in the insectary yard and other data (see p. 62), ac- 



144 



THE PLUM CURCTJLIO. 



count was taken of the emergence of this parasite from the soil boxes, 
as shown below : 

Table LXXXII. — Record of emergence of (Sigalphus) Triaspis curculionis from plum 
curculio larvse for season, Washington, D. C, 1908. 



Lot No. 


Date 

larvae 

placed in 

soil. 


Larvae 

placed in 

soil. 


Sigalphus 
emerging. 


Percent- 
age of 
larvae 

parasit- 
ized. 


Beetles 
emerging. 


Percent- 
age of 
larvae 
trans- 
forming 
to adults. 


Percent- 
age of 
larvae 
unac- 
counted 
for. 


1 


May 27 
28 
30 
31 

June 1 
o 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 

17 

18 

19 

20 

21 

22 

24 

June 25- 

Aug.l 


187 
283 
218 
297 
281 
206 
162 

90 
174 
243 
208 
203 
157 
154 
249 
369 
172 
190 
140 
296 
107 

60 
122 
106 
139 
175 
177 

800 






85 

103 

38 

25 

71 

37 

7 

24 

20 

4 

C 

5 

37 

17 

14 

84 

84 

42 

6 

52 

19 

20 

39 

31 

18 

29 

11 

185 


45.45 
36.40 
17.43 

8.41 
25.27 
17.96 

4.32 
26. 67 
11.49 

1.65 

2.88 

2.46 
23.57 
11.04 

5.62 
22.76 
48.84 
22.11 

4.29 
17.57 
17.76 
33.33 
31.97 
29.25 
12.95 
16.57 

6.21 

21.51 


54.55 


2 


2 

15 
4 

15 

10 
4 

10 
2 

15 
3 
1 
2 
3 


0.71 
6.88 
1.34 
5.34 
4.86 
2.47 
11.11 
1.15 
6.17 
1.44 
.49 
1.27 
1.95 


02.89 


3 


75. 69 


4 


90.25 


5 


69.39 


6 


77.18 


7 


93.21 


8 


62. 22 


9 


87.36 


10 


92.18 


11 


95.68 


12 


97.05 


13 


75.16 


14 


87.01 


15 . 


94.38 


16.- 


2 
4 
1 


.54 

2.33 

.53 


76.70 


17 


48.83 


18 


77.36 


19 


95.71 


20 


1 
1 
1 


.34 

.93 

1.67 


82.09 


21 


81.31 


22 


65.00 


23 


68.03 


24 


1 
3 


.94 
2.16 


69.81 


25 


84.89 


26 


83.43 


27 


1 


.56 


93.23 


28-59 






78.49 










Total 




6,025 


101 


1.68 


1,113 


IS. 47 


79.85 



The percentage of parasitism, it will be noted, varied widely — 
from less than one-half of 1 per cent to 11.11 per cent on June 4. The 
average percentage of parasitism for the season is small, and it seems 
probable that the insect during 1908 was less abundant than normal. 

Similar records of parasites emerging from lots of larvae taken over 
the whole season from Elberta peaches were made at Siloam Springs, 
Ark., during 1908, as set forth in Table LXXXIII. 

Table LXXXIII. — Record of emergence of (Sigalphus) Triaspis curculionis for season, 
Siloam Springs, Ark., 190S. 



Lot No. 



1 

2 

3 

4 

5 

6 

7 

8 

9-10 

11 

12 

13 

14-23 

Total. 



Date larvse entered soil. 



May 12-16 

May 17-19 

May 20-22 '. 

May 23-25 

May 26-28 

May 29-31 

June 1-3 

June 4-6 

June 7-12 

June 13-15 

June 16-18 

June 19-21 

June 22-Aug. 13 



Larvae. 



328 
573 
905 
550 
629 
719 
532 
449 
394 
107 
81 
61 
637 



0,025 



Sigalphus 
emerging. 



Percent- 
age of 
larvae 

parasit- 
ized. 



0.91 
3.14 
2.18 
3.45 
2.80 
.97 
.94 
.22 



3.74 
4.94 
3.28 



1.C9 



Beetles 
emerging 



50 
124 
131 
123 
253 
211 
293 
124 
102 
49 
50 
34 
230 



1,774 



Percent- 
age of 
larvae 
trans- 
forming 
to adults. 



15.24 
21.64 
13.58 
22.36 
40.22 
29. 35 
55.08 
27.62 
25.89 
45.79 
61.73 
55.74 
36.11 



29.44 



Percent- 
age of 
larvae 
unac- 
counted 
for. 



83.85' 
75.22 
S4. 27 
74.19 
56.92 
69. 68 
43.98 
72.16 
74.11 
50.47 
33.33 
40.98 
63.89 



68.87 



NATURAL. ENEMIES : PARASITIC INSECTS. 



145 



Here also the percentage of parasitism varies with the different 
lots, but is less than in case of material from Washington. The 
average parasitism for the season was 1.69 per cent, approximately 
the same as that from Washington. This would be of but little im- 
portance as affecting the abundance of the curculio. 

At Barnesville, Ga., in 1910, data of the same character were ob- 
tained from all the larvae infesting the fruit on a block of 31 Elberta 
peach trees during the season, as shown in Table LXXXIV. These 
data show a considerably higher percentage of parasitism and also a 
larger percentage of larvae transforming to adults, with a correspond- 
ing decrease in the proportion of larvae failing to produce either para- 
sites or beetles. This was doubtless due to a more favorable condi- 
tion of the soil in the rearing cages. 

Table LXXXIV. — Record of emergence of Sigalphus curculionis for season, Barnes- 
ville, Ga., 1910. 



Lot No. 


Date larvae entered 
soil. 


Number 
of larvae. 


Number 
of Sigal- 
phus 
emerg- 
ing. 


Percent- 
age 
of larvae 
parasit- 
ized. 


Number 
of beetles 
emerg- 
ing. 


Percent- 
age 
of larvae 
trans- 
forming 
to adults. 


Percent- 
age 
of larvae 

unac- 
counted 
for. 


1 

2 

3 


May 2-3 

May 4-6 

May 7-9 


77 

457 

566 

240 

209 

272 

159 

192 

142 

190 

66 

33 

28 

26 

258 


20 
96 

47 
11 
8 
11 
4 
4 
3 
7 
1 


1 



25.97 
21.01 
8.30 
4.58 
3.83 
4.04 
2.52 
2.C8 
2.11 
3.68 
1.52 


28 

182 

276 

105 

109 

170 

117 

145 

101 

108 

45 

21 

13 

15 

133 


36.36 
39.82 
48.76 
43.75 
52.15 
62.50 
73.59 
75.52 
71.13 
56.84 
68.18 
63.64 
46.43 
57.69 
51.55 


37.67 
39. 17 
42.94 


4 


May 10 


51.67 


5 


May 11 

May 12 

May 13 


44.02 


6 

7 


33.46 
23.89 


8 


May 14-16 

May 17-19 


22.40 


9... 


26.76 


10 


May 20-23 


39.48 


11 


May 24-26 

May 27-29 


30.30 


12 


36.36 


13... 


May 30- June 1 

June 2-8 




53.57 


14 


3.85 


48.46 


15 to 29 . . . 


June 9-Aug. 9 
May 2-Aug. 9 


48.45 








Total 


2,915 


213 


7.31 


1,568 


53.79 


38.90 



Observations on miscellaneous lots of larvae at Youngstown, N. Y., 
in 1905 (see Table LXXXV) show a much higher percentage of 
parasitism, the average for all lots being 18.66 per cent parasitized. 
These records, however, are not made from proportionate numbers of 
larvae throughout the season. The parasites were perhaps at their 
greatest abundance during the period under observation. 

Table LXXXV. — Record of emergence of (Sigalphus) Triaspis curculionis from miscel- 
laneous lots of larvae, Youngstown, N. Y., 1905. 



Lot No. 


Date 

larvae 

entered 

soil. 


Number of 
larvae. 


Number of 
Sigalphus 
emerging. 


Percentage 

of larvae 

parasitized. 


1 


June 27 
...do 


10 

40 

55 

80 

20 

150 

150 

126 

135 

70 


1 
8 
15 
20 
8 
35 
20 
15 
20 
14 


10.00 


2 


20.00 


3 


June 28 
June 29 
...do 


27.27 


4 


25.00 


5 


40.00 


6 


...do 


23.33 


7 


July 1 
July 2 
July 3 
July 7 


13. 33 


8 


11.90 


9 


14.81 


10 


20.00 






Total 


836 


156 


18.66 











17262°— Bull. 103—12 10 



146 THE PLUM CUECULIO. 

In reality, however, the percentage of parasitism, as shown in 
these several tables, is too low, since it is based on the total number 
of larvae which were placed in pots of soil or other container. In all 
rearing work a considerable proportion of larvae, aside from those 
killed by parasites, failed to develop to adults, from various causes, 
as immaturity, etc. Taking the total emergence of beetles and para- 
sites as a basis, the percentage of parasitism for the season of 1908 
at Washington, D. C, was 8.32; at Siloam Springs, Ark., 5.44; and 
at Barnesville, Ga., in 1910 it was 11.96. Even these figures are 
probably too low, since the removal of the infested fruit from the 
orchard to the laboratory must have prevented a certain degree of 
parasitism that would normally have occurred in fruit lying exposep 
in the orchard. 

(Sigalphus) Triaspis curculionis var. rufus Riley. 

This variety was described in his Third Missouri Report, page 27, 
by Riley, who states that it is slightly larger and differs so remark- 
ably from the normal form that were it not for the absolute corre- 
spondence of all of the sculpturing of the thorax and body, and the 
venation of the wings, it might be considered distinct. The great 
length of the ovipositor is very characteristic. Concerning this 
variety in Iowa Prof. Gillette observes (Canadian Entomologist, 
vol. 22, p. 114): 

The variety rufus appeared much more abundant than curculionis in my breeding 
cages last summer. The two forms differ so much from one another, and in some 
respects, especially in the number of joints of the antennse, from Riley's description 
that I have made the following notes upon them: " * * * Rufus is decidedly more 
robust in every case than curculionis, and were it not for the fact that so eminent an 
authority as Dr. Riley considers them the same species, I should think that rufus 
ought to be raised to the rank of a species." 

Attempts were made by Prof. Riley to distribute both the Sigal- 
phus and Porizon parasites, specimens being sent to several corre- 
spondents from Kirkwood, Mo. In the bureau collection of Sigal- 
phus reared from the curculio, 725 specimens, only 40 are of the 
rufus variety, from the following localities: Fort Valley, Myrtle, and 
Barnesville, Ga.; Valparaiso, Ind.; Arlington, Va.; Riverdale, Md.; 
Washington, D. C, and Siloam Springs, Ark. These, with its 
recorded occurrence in Missouri and Iowa, indicate a distribution 
similar to that of curculionis. 

It appears from observations made at Barnesville, Ga., in 1910 
that while practically all of the typical forms emerge from the 
earliest larvae, the variety rufus only reaches its full numbers very 
late in the season, after curculionis has ceased to appear. A few 
isolated specimens of rufus emerged in connection with the typical 
form from material from Elberta peaches, but most of them were 



NATURAL ENEMIES: PARASITIC INSECTS. 



147 



reared much later from other material. From 240 curculio larvae 
which entered the soil August 30 to October 15 there emerged 16 
specimens of rufus from September 24 to October 23. This gives a 
percentage of parasitism of 6.66. No other kinds of parasites emerged 
from these late larvae, while the proportion and number of rufus were 
larger than at any previous time. 

(Porizon) Thersilochus conotracheli Riley. 

This ichneumonid "parasite of the curculio (see fig. 27) was 
described by Riley in 1871 (Third Missouri Report, p. 28) from speci- 
mens reared from cocoons sent him by Dr. Trimble, of New Jersey. 
The parasite feeds upon the curculio larva, and while developing 
to the adult form in the fall, remains in the cocoon until the following 
spring. This habit of overwintering in the soil perhaps has con- 
tributed to its general oversight by persons who have reared cur- 
culios, for there are very few references in literature concerning it. 
Five specimens of adults of this 
species were dissected from cocoons 
by Mr. Johnson, at Youngstown, 
N. Y., August 24 and October 2, 
1908, and on October 4 of the same 
year a total of 76 cocoons of this 
parasite was found in curculio rear- 
ing jars, in which had been placed 
a total of 836 curculio larvae, giv- 
ing a percentage of parasitism for 
this species of 9.09. Mr. John- 
son also succeeded in rearing this 
species from material kept over 
winter. On October 5, 1905, 55 cocoons were found in a jar for 
breeding curculios at Youngstown, N. Y. This jar was again exam- 
ined May 18, 1906, by which time 11 adult parasites had emerged. 
Forty-eight cocoons were found in a jar in which had been placed 549 
curculio larvae, at North East, Pa., August 24, 1906. 

Dr. Riley evidently reared this species, along with (SigalpJius) 
Triaspis curculionis, in numbers in Missouri, for he speaks of having 
distributed specimens of each, from Kirkwood, to several localities. 
The insect is recorded by Dr. Howard from Coon Island, Pa., in 
1887, and Riley and Howard (Rept. Com. Agr., 1888, p. 64) refer 
to receipt of specimens from a correspondent who found them ovi- 
positing and regarded them as a new enemy of the plum. Prof. 
Gillette, in his curculio studies in Iowa, makes no reference to Pori- 
zon, which presumably was not observed. The species is probably 
of much less economic importance than the preceding, though, as 




Fig. 27. — (Porizon) Thersilochus conotracheli, 
parasitic upon the plum curculio: a, Fe- 
male; 6, male. (From Riley.) 



148 



THE PLUM CURCULIO. 



stated, its habit of wintering in the cocoon may have caused it to 
have been overlooked. Specimens are in the U. S. National Museum 
from Long Island and Oswego, N. Y., Connecticut, southern Illinois, 
Missouri, and Onaga, Kans. 

(Bracon) Microbracon mellitor Say. 

A specimen of (Bracon) Microbracon mellitor (fig. 28) was reared from 
the plum curculio by Prof. F. E. Brooks at French Creek, W. Va., in 
1902 (U. S. Dept. Agr., Div. Ent., Bui. 38, n. s., p. 109). In 1905 it was 
again reared from the plum curculio at Youngstown, N. Y., North East, 

Pa., Arundel, Md., and 
Fort Valley, Ga. Observa- 
tions by Mr. Fred Johnson 
at Youngstown,N. Y., and 
North East, Pa., indicate 
that this parasite lives ex- 
ternally upon the curculio 
larva, destroying the lat- 
ter before it leaves the 
fruit. The cocoon of the 
parasite is then formed 
within the fallen fruit. 

Bracon dorsata Say. 

Several specimens of this 
insect were reared from 
curculio - infested plums 
from Arundel, Md., Wash- 
ington, D. C, and Lexington, Ky. Other insects were also present, 
and there is a doubt that this species is a parasite of the plum curculio. 

Other Hymenopterous Parasites. 

A chalcidid of the genus Eurytoma was reared from Conotrachelus 
nenuphar at French Creek, W. Va., in 1902 (U. S. Dept. Agr., Div. 
Ent., Bui. 38, n. s., p. 109). At North East, Pa., 4 specimens of a 
species of Anisocyrta (Braconidse) emerged, July 24, 1906, from the 
soil in a jar in which curculio larvse were transforming. An ichneu- 
mon fly, Pimpla (Epiurus) sp., was also reared at North East, Pa., 
from curculio-infested prunes, 3 specimens emerging July 9-23, 1906. 
What is very likely the same species was reared at Youngstown, N. Y., 
in 1905. The parasite destroyed a curculio larva in a small apple 
and formed a cocoon in the dropped fruit. At Vienna, Va., during 
1911, Mr. K. A. Cushman reared the following from the curculio: 
Eurytoma sp., Catalaccus sp., Cerambycobius sp., and Microbracon lixi 
Ashm., which was next in abundance to Triaspis curculionis. 




Fig. 28. — (Bracon) Microbracon mellitor, an occasional parasite 
of the plum curculio. (From Hunter and Hinds.) 



NATURAL ENEMIES: PARASITIC INSECTS. 149 

Myiophasia eenea Wiedemann. 

This tachinid fly (fig. 29) is a widely distributed parasite of the 
larvae of several species of weevils, including the plum curculio. 
It is a very variable species, having been described and recorded 
under many names. The species was first described from Monte- 
vidio, Uruguay, South America, but has since been found in Central 
America, Mexico, and all sections of the United States. In the col- 
lections of the National Museum and the Bureau of Entomology there 
are specimens from the following localities: Chinandega, Nicaragua; 
City of Mexico, Mexico; Sierra Madre, Chihuahua, Mexico; Pecos, 
N. Mex. ; Beulah, N. Mex. ; Corvallis, Oreg. ; St. Louis, Mo. ; Dallas, 
Tex.; Baton Rouge, La.; Inverness, Fla. ; Tifton, Ga. ; Barnesville, 
Ga.; Clemson College, S. C; Arundel, Md.; White Mountains, N. H.; 
Douglas, Mich. 

Other recorded localities are: Santa Fe, N. Mex.; Charlotte Har- 
bor, Fla.; New Jersey; Massachusetts; Gypsum, Ohio; Constantine, 
Mich. ; Carlinville, 111. ; South Dakota. 

It is thus seen that the species extends greatly beyond the range 
of the plum curculio, subsisting on other hosts. Riley, Lugger, and 
Pergande reared Myiophasia senea 
from Balaninus uniformis Lee, at 
St. Louis, Mo., in 1876. In 1886 
Pergande reared it at Washington, 
D. C, from Conotrachelus elegans Say, 
infesting young twigs of hickory. 
Parasites reared by Forbes from 
Sphenophorus parvulus Gyll., and 
a cutworm (Heliophila unipuncta 
Haw.) were identified under one of 
the synonyms of M. senea (Psyche, FlG 29 ._ Myiopha , ia xnea> a dipterous plum 

Vol. 6, p. 467), but it is probable that curculio parasite: Male and head of female. 

,-i • ]• •, (Froin Ainslie.) 

there was an error m recordmg it as 

a parasite oiHeliophila unipuncta, there being no other known instance 
of M. senea attacking anything but weevil larvae. At Gypsum, Ohio, 
Webster found M. senea as a parasite of Ampeloglypter sesostris Lee. 
(Ent. News, vol. 10, p. 53, pi. 3). In this case a secondary para- 
site (Calyptus tibiator) was reared from M. senea. More recently 
Pierce (Journ. Econ. Ent., vol. 1, p. 381) has reared M. senea from 
the boll weevil (Anihonomus grandis Boh.) and from Conotrachelus 
elegans Say at Dallas and Victoria, Tex. In the National Museum 
are many specimens of M. senea reared from Chalcodermus seneus 
Boh. by G. G. Ainslee, Clemson College, S. C. It had previously 
been reared from a species of Chalcodermus by H. A. Morgan at 
Baton Rouge, La. 




150 THE PLUM CTJRCTJLIO. 

So far as known M . senea was first obtained as a parasite of the 
plum curculio by Mr. A. A. Girault, who reared a single specimen 
from curculio-infested peaches collected at Arundel, Md., June 29, 
1905. In 1908 another specimen was reared from the plum curculio 
in cherries by R. W. Braucher at Douglas, Mich. At Barnesville, 
Ga., 13 specimens were reared from 1,115 curculio larvae from peaches 
collected on August 5, 1910. The larvae entered the soil August 6 
to 13, and the parasites emerged from August 29 to September 5. 
This species must be considered as only an occasional parasite of the 
plum curculio, the highest known percentage of parasitism being 
1.16 in the case of the lot reared at Barnesville, Ga. A few speci- 
mens of this fly were reared from curculio larvae by R. A. Cushman 
during 1911, at Vienna, Va. 

Cholomyia inaequipes Bigot. 1 

Like the preceding species, Cholomyia insequipes (fig. 30) is a very 
widely distributed parasite of weevil larvae. It was first described 
by Fabricius from South America in 1805 as Musca longipes, and 
later by Bigot from Mexico under the name of C. insequipes. Speci- 
mens are in the National Museum and in the Bureau of Entomology 
collections from the following localities: Frontera, Tabasco, Mexico; 
Dallas, Tex.; Lawrence, Kans.; St. Louis, Mo.; Siloam Springs, Ark.; 
Mound, La.; Fort Valley, Ga.; Barnesville, Ga.; Peaks of Otter, Va.; 
Arlington, Va.; Arundel, Md.; Lexington, Ky. ; West Virginia; 
North East, Pa. 

This insect was first reared by Riley at St. Louis, Mo., under cir- 
cumstances indicating that it was a parasite of the plum curculio. 
In 1897 it was reared at Mound, La., from Conotrachelus juglandis 
Lee. Metadexia basalis Giglio-Tos, which Mr. D. W. Coquillett regards 
as probably a synonym of C. insequipes, has been reared from Cono- 
trachelus juglandis in West Virginia. Pierce has reared C. insequipes 
from Conotrachelus elegans Boh., at Dallas, Tex. At Siloam Springs, 
Ark., it has been reared from Conotrachelus affinis Boh. 

The Bureau of Entomology has records of the rearing of this species 
from the plum curculio as follows: 

Arundel, Md., July 13, 1905, 1 specimen (plum). 

Arlington, Va., August 14, 1905, 1 specimen (peach) 

Fort Valley, Ga., October 1, 1905, 1 specimen (Crataegus). 

North East, Pa., July, 1906, several specimens. 

Siloam Springs, Ark., July to August, 1908, 4 specimens (peach). 

Barnesville, Ga., June 20 to September 15, 1910, 81 specimens (peach). 

1 Concerning the synonymy of this species, Mr. D. W. Coquillett has stated that longipes as a specific 
name for this dexidid is preoccupied by Musca longipes Fab. (1794), an entirely different insect from the 
present one, also described by Fabricius under the same name in 1805. The species, therefore, had no 
distinctive name in 1805, and must take the name given it by Bigot in 1884. The synonyms of Cholomyia 
insequipes Bigot (1884) are Musca longipes Fab. (1805) (not 1794), and Thelairodes basalis Giglio-Tos (1893). 



NATURAL ENEMIES : PARASITIC INSECTS. 



151 



In the last instance, at Barnesville, Ga., 74 of these parasites were 
reared from 1,115 curculio larvae from peaches, entering the soil 
August 6 to 13. The parasites from this lot emerged August 30 to 
September 15, the females emerging slightly later than the males on 
an average. In this case the percentage of parasitism by O. inse- 
quifes was 6.63. 




Fig. 30.- 



-Cholomyia insequipes, a fly reared abundantly from the plum curculio at Barnesville, Ga.: Adult 
on left, puparium in curculio larval skin on right. (Original.) 



The puparium of Cholomyia (fig. 30) is formed in the soil, within 
the skin of the host larva, the adult parasite, on emerging, breaking 
through the posterior end of the old skin. 

Pegomya fusciceps Zett. 

This anthomyiid fly has appeared many times in jars and cages in 
which the plum curculio was being reared. But it is unlikely that 
this species is ever parasitic, and its presence may in most cases be 
accounted for as a feeder upon the more or less decayed fruit in com- 
pany with the curculio larvae. 



152 THE PLUM CUECULIO. 

PREDACEOUS INSECTS. 

Several species of predatory insects are recorded as attacking the 
curculio, especially in the larval stage, though their importance is 
difficult to estimate. In our own investigations ants have been 
found to be efficient enemies of curculio larvae as they are leaving the 
fruit and entering the soil. Numerous observations in peach orchards 
in Georgia show that these creatures are ever on the alert for an 
insect as food, and seek out and quickly destroy curculio larvae or 
other soft-bodied insects. Mr. Girault, and also Mr. Rosenfeld, 
record frequent observations of ants attacking larvae in the course of 
breeding work at Myrtle, Ga., interfering greatly with the experi- 
ments. Thus on June 16 a large number of larvae were placed on the 
soil in a box for pupal records. These, however, were soon dis- 
covered by the ant, Dorymyrmex pyramicus Roger, which destroyed 
numbers of larvae before they could be driven off. Within a quarter 
of an hour ants were literally swarming over the soil, in the box, 
and very few larvae succeeded in getting any distance into the soil 
before being attacked and destroyed. 

In the course of timing larvae in entering the soil in cultivated 
orchards, these were often found and attacked by one or more ants 
(Dorymyrmex pyramicus Roger), usually with fatal results to the 
larva. Thus, a larva placed on the soil at 4.23 p. m. (May 30, 1906) 
was attacked eight times in succession by ants, which were repelled 
each time, but succeeded at the ninth attack — at 4.33 p. m. This 
species is especially common in Georgia orchards, and in the aggre- 
gate must exert an important influence in destruction of the curculio. 

A species of thrips is recorded by Riley (2d Mo. Rept., p. 6) as very 
effective in destroying the eggs of the curculio. 

Mr. Walsh, in an interesting article in the American Entomologist 
for 1868, page 33, gave observations on certain insects regarded by him 
as predatory on the curculio. These observations are given by Riley 
in his Missouri Report (p. 56), and the substance appears in Riley and 
Howard's well-known article on the "Plum curculio." There can 
be no doubt whatever as to the accuracy of Mr. Walsh's observations, 
but practically nothing has since been added to our knowledge of the 
usefulness of these insects in destroying the curculio 

A larva of a species of lacewing (Chrysopa) was observed by Walsh 
in one side of a peach badly bored by a curculio. It was actually 
feeding upon a curculio larva, one-half of which had already been 
sucked dry. One of these insects is shown in figure 31. They are 
well known to feed upon various soft-bodied insects, especially 
plant-lice. 

A carabid beetle, Aspidoglossa subangularis Chaud., was found inside 
a peach completely excavated by the curculio, from which Mr. Walsh 
concluded that this species also was an enemy of the curculio. These 
two species were regarded as undoubtedly predatory on the curculio 



NATURAL ENEMIES; PREDACEOUS INSECTS. 



153 



above ground, and the larva of a ground beetle was found by a Mr. 
Swing in loose earth under peach trees in large numbers, which Mr. 
Walsh believed searched out the insects in the ground. 




Fig. 31. — Chrysopa oculata. 



Species of Chrysopa are recorded as predaceous on the plum curculio. 
Marlatt.) 



(From 



Four other species of ground beetles were found which were believed 
to attack the curculio grubs, although known to be general feeders, 
namely, Harpalus pennsylvanicus De Geer (fig. 32), H. f annus Say, 




Fig 32.— Harpalus pennsylvanicus, a ground beetle predatory upon the plum curculio. (From Webster.) 



154 THE PLUM CURCULIO. 

Evarthrus orbatus Newman, and E. obsoletus Le Conte. The first 
mentioned (H. pennsylvanicus) was noted to be especially abundant, 

" absolutely swarming in all di- 

». + rections underground," and was 
YQC \) thought to be the parent of the 
f 6 J Imf larva earlier alluded to. Walsh 
MM JifPl ^us recor( is 6 different species 
Till? °^ msec * s J ^ of which fed upon 
J? ^ S^ the curculio, while the remaining 
4 were strongly suspected of so 

Fig. 33. — Chauliognathus pennsylvanicus. The larva doing. An additional Species 
of this beetle is recorded as a very effective enemy / n-i 7 • .t 7 • \ 

of the pi um curculio. (After Riley.) (Chauliognathus pennsylvanicus) 

(fig. 33) in the larval stage was 
found in curculio-injured peaches, and actually observed to feed 
upon the curculio grub by Mr. Swing, who forwarded the specimens 
to Walsh. 

FOWLS AND BIRDS AS CURCULIO DESTROYERS. 

The value of chickens and other fowls in checking the curculio has 
been alluded to by several writers, notably the older ones. There is 
practically no definite observation, however, to show to what extent 
fowls feed upon these insects. Without doubt, in orchards fre- 
quented by chickens many of the beetles and possibly the larvae 
as they are leaving the fruit are found and eaten, but the good 
influence of fowls in this way is at most small, and confined prin- 
cipally to the vicinity of the house. 

On the importance of birds as curculio destroyers, there are but 
few data. Dr. Isaac Trimble was probably first to record that the 
Baltimore oriole will feed upon this insect, which fact has been con- 
firmed by subsequent observations. 

The Bureau of Biological Survey of the United States Department 
of Agriculture has found plum curculio beetles in the stomachs of 7 
species of birds, namely: Baltimore oriole (Icterus galbula), Windsor, 
Ont.; orchard oriole (Icterus spurius), Atlanticville, N. Y., Chester 
County, Pa., Marshall Hall, Md.; rose-breasted grosbeak (Zamelodia 
ludoviciana) , Portland, Conn.; bank swallow (Riparia riparia), Sing 
Sing, N. Y.; yellow-throated vireo (Lanivireo jlavifrons), Sing Sing, 
N. Y.; veery (Hylocichla fuscescens) , Syracuse, N. Y.; hermit thrush 
(HylocicMa g. pallasi), Washington, D. C. 

Dr. Trimble states also that he found this insect in the stomach of 
a toad. 



THE PLUM CURCULIO. 155 

REMEDIAL MEASURES. 
HISTORICAL. 

Measures for the control of the plum curculio have occupied the 
attention of fruit growers from the earliest times, and the total writ- 
ings on this subject in various horticultural, farm, and other journals 
w^uld comprise a very large volume. The curculio, being native, 
soon attacked the choice fruits planted by the pioneer settlers, and 
accounts of its depredations soon found their way to print. The 
insect was especially complained of by reason of its injuries to plums, 
and the culture of this fruit seems to have been attended with the 
greatest difficulty. Many persons, if we are to judge from the earlier 
accounts, gave up the fight in despair, cutting down the trees. Dur- 
ing practically all of the last century a succession of remedies was 
proposed, and much discussion resulted as to their merits. Most of 
them were of but little if any value, and some of those proposed were 
actually absurd. The plan of jarring, or "shaking," as it was gen- 
erally designated, is practically the only one which survived of the 
innumerable ones proposed. The employment of arsenicals against 
the curculio marked a distinct advance, though until recently their 
use on stone fruits had not become very general on account of injury 
to foliage and fruit. 

As indicating the feelings of the early fruit growers toward the 
curculio, and their efforts to circumvent its injuries, several of the 
earlier accounts of the insect are inserted. These articles possess 
distinct historical interest, for in but few instances is it possible 
to follow from so early a date the gradual increase of an insect in 
importance as a pest, along with the increase in plantings of its host 
plants. The remedies proposed were legion, and about as varied as 
the nostrums proposed for some human ailment, as rheumatism. 
While no special effort has been made to list all the early remedial sug- 
gestions, the following have been noted : 

Seaweed under the trees; stable manure spread under trees; thor- 
ough whitewashing of trees; air-slaked lime dusted on trees in early 
morning while wet with dew, after setting of fruit; fumigation with 
sulphur fumes; wood ashes thrown over trees during blossoming 
when wet with dew; sulphur and powder fired from a gun into the 
top of trees for a few successive mornings; sulphur, lard, and Scotch 
snuff mixed and rubbed on trunk and larger branches ; drenching the 
tree with putrid soapsuds, followed by dusting with lime; flowers of 
sulphur sprinkled over trees after setting of fruit; sulphureted hy- 
drogen generated from calcium sulphid; packing the earth under 
the trees; tobacco smudge; hanging in trees putrid flesh, as dead 
mice, etc., to be used by the beetles for ovipositing; burning leather 



156 THE PLUM CUECULIO. 

under trees on pans of charcoal; soft soap placed in crotches of 
limbs ; burning soot under trees ; paving the earth under trees with 
brick, slate, mortar, etc.; branches of tansy hung in trees; burning 
under trees woollen rags saturated with brimstone; destroying the 
eggs in the fruit by means of a needle-like instrument; passing 
around the trees a blazing straw torch, into which the beetles 
would fly; protecting the fruit with mosquito netting; confining 
in the orchard pigs, geese, poultry, etc.; fencing out the curculio 
with a high, 9-foot fence; fall plowing; liberal use of salt around 
the trees; removal of surface of soil and contained insects from around 
base of trees; covering soil with salt during midsummer to kill 
worms escaping from the fruit; picking up and destroying stung 
fruit; dilute sulphuric acid thrown on the soil to destroy insects in 
ground ; bruising the tree to cause exudation of gum to prevent its 
development on the fruit upon which the larvae feed; removal and 
destruction of black-knot disease; flooding the soil to drown insects; 
placing quicksilver in holes bored in trunk of trees; corrosive subli- 
mate thrown into the soil to destroy the insects in the ground; jarring 
insects onto sheets held or placed under trees; asafoetida spray; 
whale-oil soap, sulphur, lime-and-tobacco spray; coal-tar and water 
spray; piles of small stones around trees; trapping curculio under 
chips, small boards, etc., placed on the ground under the trees; 
planting of nectarines as a trap crop; light traps; belts of cotton 
batting around the trees; lead-pipe troughs around the trees filled 
with oil; hanging in trees bottles of sweetened water as a bait. 

The first remedial suggestions which we have seen are those in 
Darlington's Memorial, giving the correspondence between the early 
American botanist, John Bartram, and his patron, Peter Collinson. 
Under date of March 14, 1736-37, Peter Collinson, writing to John 
Bartram, refers x to the — 

very particular account how your plums are destroyed by an insect. Pray change 
the stock, and graft plums and nectarines on peach stocks, which being a vigorous, 
free stock, and not liable to these insects, may succeed better. Pray try; I have a 
great opinion of its succeeding. 

That the above referred to the plum curculio is evident from a 
later communication. John Bartram, writing under date of April 
16, 1746, and speaking of the strawberry and sloe, the last of "which 
we have had in the country these 50 years. I plant them about my 
hedges, where it grows to a large size. The blossoms are prodigious 
full, but never one ripe fruit. They were bit by the insect, as all our 
stone fruit is ; but the peaches, and some kinds of cherries, overgrow 
them." 2 In a letter under date of April 24, 1746, Peter Collinson, 
in writing to John Bartram, adds: 

To prevent the destruction of the beetle, I confess, is not so easy as some other bad 
effects; yet as we know the duration of this insect is but short, if while he is so noxious, 

i Darlington's Memorial, p. 93. 2 Darlington's Memorial, p. 175. 



REMEDIAL MEASURES: HISTORICAL. 157 

some contrivance could be found out to disturb or destroy him, you might then hope 
to taste a nectarine — one of the most delicious fruits in the universe, and much 
exceeds a peach, in a rich vinous-flavored juice. And an apricot is also one of the 
fine fruits. Last year our standards were overloaded, which were allowed to excel 
the wall fruit. 

Suppose as soon as this beetle is discovered if the trees were to be smoked, with 
bur 1 Ing straw under them or at some distance, so as to fumigate their branches at a 
timb the beetles are most liable to attack the fruit, or if the trees were to be squirted 
on with a hand engine with water in which tobacco leaves were soaked; either of 
these two methods, I should think, if they did not totally prevent, yet at least would 
Becure so much of these fine fruits as would be worth the labor of people of circum- 
stances who are curious to taste these delicious fruits in perfection. 

I take it the reason the plum succeeds so well is the frequent shaking of the trees 
by being planted in a frequented place. The beetles are tumbled off, or else are 
disturbed and frightened from settling on the trees. 

The earliest extended account of the insect is that by Dr. James 
Tilton, of Wilmington, Del., in Willich's Domestic Encyclopaedia 
(vol. 3, p. 116), published in 1804. This original article shows a 
considerable familiarity with the curculio, and was much quoted by 
subsequent writers. Some of the methods suggested for control 
later came into much notoriety and use. This comparatively inac- 
cessible article is here reproduced: 

Curculio, a genus of insects belonging to the Coleoptera, or beetle order. The 
species are said to be very numerous. The immense damage done, by an insect of 
this tribe, to the fruits of this country, of which there is no similar account in Europe, 
has given rise to a conjecture with some naturalists, that we have a peculiar and very 
destructive species in America. 

The manner in which the insect injures and destroys our fruits, is, by its mode of 
propagation * * *. Early in the spring, about the time when the fruit trees are 
in blossom, the Curculiones ascend in swarms from the earth, crawl up the trees, and 
as the several fruits advance they puncture the rind or skin, with their pointed rostra, 
and deposit their embryos in the wounds thus inflicted. The maggot thus imbedded 
in the fruit preys upon its pulp and juices, until in most instances, the fruit perishes, 
falls to the ground and the insect escaping from so unsafe a residence, makes a sure 
retreat into the earth: where, like other beetles, it remains in the form of a grub or 
worm, during the winter, ready to be metamorphosed into a bug or beetle, as the 
spring advances. Thus every tree furnishes its own enemy; for although these bugs 
have manifestly the capacity of flying, they appear very reluctant in the use of their 
wings; and perhaps never employ them but when necessity compels them to migrate. 
It is a fact that two trees of the same kind may stand in the nearest possible neighbor- 
hood, not to touch each other, the one have its fruit destroyed by the curculio, and 
the other be uninjured, merely from contingent circumstances, which prevent the 
insects from crawling up the one, while they are uninterrupted from climbing the 
other. 

The curculio delights most in the smooth skinned stone fruits, such as nectarines, 
plums, apricots, etc., when they abound on a farm; they nevertheless attack the 
rough-skinned peach, the apple, pear, and quince. The instinctive sagacity of these 
creatures directs them especially to the fruits most adapted to their purpose. The 
stone fruits more certainly perish by the wounds made by these insects, so as to fall 
in due time to the ground, and afford an opportunity to the young maggot to hide 
itself in the earth. Although multitudes of seed fruits fall, yet many recover from 



158 THE PLUM CUECULIO. 

their wound, which heal up with deeply inflicted wounds * * *. This probably 
disconcerts the curculio, in its intended course to the earth. Be this as it may, certain 
it is, that pears are less liable to fall, and are less injured by this insect than apples. 
Nectarines, plums, etc., in most districts of our country, where the curculio has gained 
an establishment, are utterly destroyed, unless special means are employed for their 
preservation * * *. Cherries escape better, on account of their rapid progress to 
maturity and their abundant crops: the curculio can only puncture a small part oi 
them, during the short time they hang upon the tree. These destructive insects 
continue their depredations from the first of May until autumn. Our fruits collec- 
tively estimated must thereby be depreciated more than half their value. 

It is supposed the curculio is not only injurious above ground, but also in its retreat, 
below the surface of the earth, by preying on the roots of our fruit trees. We know 
that beetles have, in some instances, abounded in such a manner as to endanger whole 
forests. Our fruit trees often die from manifest injuries done to the roots by insects, 
and by no effect more probably than the curculio. In districts wherein the insect 
abounds, cherry trees and apple trees, which disconcert it most above, appear to be 
the special objects of its vengeance below the surface of the earth. 

These are serious evils; to combat which, every scientific enquirer is loudly called 
upon to exert his talents; every industrious farmer to double his diligence, and all 
benevolent characters to contribute their mite. 

Naturalists have been accustomed to destroy vicious insects, by employing their 
natural enemies to devour them * * *. (See Blight.) 

We are unacquainted with any tribe of insects able to destroy the curculio. All 
the domestic animals, however, if well directed, contribute to this purpose. Hogs 
in a special manner are qualified for the work of extermination. This voracious 
animal, if suffered to go at large in orchards, and among fruit trees, devours all the 
fruit that falls, and among others the curculiones, in the maggot state, which may 
be contained in them. Being thus generally destroyed in the embryo state, there 
will be few or no bugs to ascend from the earth in the spring, to injure the fruit. Many 
experienced farmers have noted the advantage of hogs running in their orchards. 
Mr. Bordley, in his excellent "Essays on Husbandry" takes particular notice of the 
great advantage of hogs in orchards ; and although he attributes the advantage derived 
from these animals to the excellence of their manure, and their occasional rooting 
about the trees, his mistake in this trivial circumstance does by no means invalidate 
the general remarks of this acute observer. The fact is, hogs render fruits of all kinds 
fair and unblemished, by destroying the curculio. 

The ordinary fowls of a farm yard are great devourers of beetles. Poultry in gen- 
eral are regarded as carnivorous in summer, and therefore cooped sometime before 
they are eaten. Everybody knows with what avidity ducks seize on the tumble bug 
(Scarabseus carnifex), and it is probable the curculio is regarded by all the fowls as 
an equally delicious morsel. Therefore, it is, that the smooth stone fruits particularly 
succeed much better in lanes and yards, where the poultry run without restraint than 
in gardens and other enclosures, where the fowls are excluded. 

Even horned cattle and all sorts of stock may be made to contribute to the preserva- 
tion of our valuable fruits. By running among the trees they not only trample to 
death multitudes of these insects ; but by hardening the ground, as in lanes, it becomes 
very unfit to receive or admit such tender maggots as crawl from the fallen fruits. 
Besides, the curculio is very timid, and when frightened by the cattle rubbing against 
the tree or otherwise, their manner is to fold themselves up in a little ball and fall 
to the ground; where they may be trampled and devoured by the stock, poultry, etc. 
Col. T. Forest, of Germantown, having a fine plum tree near his pump, tied a rope 
from the tree to his pump handle, so that the tree was gently agitated every time 
there was occasion to pump water. The consequence was that the fruit on this tree 
was preserved in the greatest perfection. 



REMEDIAL MEASURES : HISTORICAL. 159 

All the terebinthinate substances, with camphor and some others, are said to be 
very offensive to insects generally. Upon this principle, General T. Robinson, of 
Naaman's Creek, suspends annually little bits of board, about the size of a case knife, 
dipped in tar, on each of his plum trees * * *. From three to five of these strips 
are deemed enough, according to the size of the tree. The General commences his 
operations about the time or sooner after the trees are in full bloom, and renews the 
application of the tar frequently, while the fruit hangs on the tree. To this expedient, 
he attributes his never failing success. Other gentlemen allege, that common turpen- 
tine would be still better; being equally pungent and more permanent in its effects. 
Som have sown offensive articles, such as buckwheat, celery, etc., at the root of the 
tree, and have thought that great advantage followed. 

Ablaqueation, or digging round the trees, and making bare their roots in winter is 
an old expedient of gardeners for killing insects, and may answer well enough for a 
solitary tree, a year or two; but the curculio will soon recover from a disturbance of 
this sort, and stock the tree again. 

There is no surer protection against the curculio than a pavement. This, however, 
is only applicable to a few trees. It may serve in town; but will not answer in the 
country * * *. (Flat stones, however, may be placed around the tree, and where 
lime is at hand, they may be cemented.) 

Many other expedients, such as smoking, brushing, watering, etc., may be suc- 
cessfully employed, for the protection of a favourite tree or two; but it is manifest 
from the preceding history, that a right disposition of stock, especially hogs, among 
the fruit trees, can only be relied on by a farmer, with orchards of considerable exter/;. 
And that the stock, poultry, etc., may perform the task assigned them, it is evident, 
that a proper disposition of fruit trees is essentially necessary. 

As the smooth stone fruits are the grand nurseries of the curculio, special care 
should be taken to have these effectually protected. Unless this can be done, a 
farmer should not suffer them to grow on his plantation. He will derive no benefit 
from them; and they will furnish a destructive vermin that will ruin his other fruits. 
Cherry trees, nectarines, plums, apricots, etc., should therefore be planted in lanes 
and hard beaten yards (or paved yards), the common highways of all the stock of 
the farm, and not beyond the range of the ordinary domestic fowls. Orchards of apple 
trees, pear trees, peach trees, etc., should be in one enclosure. The pear trees and 
peach trees may occupy corners of the whole design, so as occasionally to be fenced 
off. In large orchards, care should be taken that the stock of hogs is sufficient to eat 
up all the early fruit which fall from May until August. This precaution will be more 
especially necessary in large peach orchards: for, otherwise, when the hogs become 
cloyed with the pulp of the peach, they will let it fall out of their mouths and content 
themselves with the kernel, which they like better; and thus the curculio escaping 
from their jaws may hide under ground, until next spring. Solitary trees of one 
fruit or another, remote from the orchard, should be regarded as nurseries of the 
curculio, and ought to be cut down or removed to the common enclosure. A young 
orchard should not be planted in the place of, or adjacent to an old one; that it may 
not be immediately infested with the curculio. 

It is also apparent, from what has been said, that great advantages might result from 
an association or combination of whole neighbourhoods against this common enemy. 
Although an intelligent farmer may accomplish much, by due attention, within his 
own territory, the total extermination of the curculio can hardly be expected, but by 
the concurrent efforts of whole districts. 

(On this subject it may be added, that a gardener near Baltimore, who has been 
successful in raising plums, finds that .the insect does most mischief in the night; 
and hence he shakes the tree every evening, and catches the insect in a sheet around 
it. He always burns them instantly. Wrapping each plum in a muslin bag, or in 
thin paper perforated with a pin, is a certain, though troublesome, mode of guarding 
against the attacks of these insects.) 



160 THE PLUM CUECULIO. 

William Bartram, an eminent naturalist of Philadelphia, in a 
communication to the Philadelphia Society for Promoting Agricul- 
ture, for 1807, after a description of the curculio, goes on to say: 

During my travels from Pennsylvania to Florida I had sufficient opportunity to 
observe that the fruit trees on the sea coast and brackish water were free from the 
ravages of this destructive insect; this suggested to me an idea, that the saline vapors 
were pernicious to them, and thus I imagine that if we were to go to the trifling ex- 
pense of showering our choicest fruit trees with a weak solution of common sea salt, 
once or twice a week, it might answer the same end of preserving the fruit; and by per- 
severing further in a little more expense, in extending the same care to our orchards, 
we might in a few years expel them. But this is only a conjecture, having never made 
the experiment. 

In the beginning of the year 1808, he added the following note: 

The spring following I put the experiment on showering a plum tree on trial, with a 
weak solution of sea salt dissolved in water; but being too strong of salt, most of the 
leaves and fruit fell off on consequence of it, otherwise the experiment might have 
produced the desired effect, as what fruit remained was not touched by the insect, 
though small and disfigured by the strength of the brine; yet a few arrived to their 
natural size and ripened, so that I am induced to believe, that with care in tempering 
the solution, it will be found to be the best and cheapest remedy against the ravages 
and increase of those pernicious insects, yet discovered. It should be so weak as just 
to taste of salt. 

Joseph E. Muse, writing in the American Farmer, volume 1, No. 
16, page 124, under date of July 16, 1819, under the caption "Ento- 
mology," treats among other insects, the curculio, as follows: 

Another insect, the curculio, of which there are nearly one hundred species, belong- 
ing also to the Coleopterous order, commands, from its universal ravages both upon the 
farmer and the fruiterer, the attention of every member of the community, who has it 
in his power to contribute, in the smallest measure, to the destruction of this ruthless 
foe to the wealth and luxury of man; which frustrates, by its concealed and wily move- 
ments, the most rational and well founded plans, executed by the most ardent and 
efficient energies of the human mind and body. Are we not inclined to exclaim,with 
the moral and philosophical Seneca, " Natura quam te colimus inviti quoque." How 
repugnant to the proud feelings of man to stoop to combat with this insignificant 
animalcule! How resistless are the ordinances of nature, which compel us, by acts 
so humiliating, to admire and adore that complex creation whereby the great architect 
has seen fit to enforce them ! 

I have made experiments on the larvae of several species of curculiones, and have 
found the parents so nearly similar in habitat, metamorphoses, and most other circum- 
stances, that one description will suffice for their whole history; at least of those which 
I have examined; and the only mark of idiocrasy in the tribes which I have observed, 
consists in their choice of a nidus; selecting, from their peculiarities in this respect 
alone, the cherry, the plum, or the grain of corn, as their instinctive or innate 
propensities might incline them. 

In a transparent bottle containing some earth, I deposited several cherries, in which 
were the larvae of the curculio, that infests that fruit; in a few weeks, or rather as soon 
as the pulp of the fruit was consumed, which was at different periods, they retreated 
into the earth where upon examination some time after, I found they had assumed the 
3tate of chrysalis, which shortly resulted in that of the imago or parent; the wings of 
the insect were not sufficient to accomplish the flight of the insect, but merely to assist 



REMEDIAL MEASURES: HISTORICAL. 161 

its ascent of the body of a tree; from which circumstances, I was led to the following 
reflections and experiments to test their correctness: 

That the remedy must be such as would act, physically, to wit: To interrupt the 
metamorphoses, by preventing the descent of the larvae into the earth; to expose to 
the weather, the pupa, after its descent; or to intercept in its ascent of the body of 
the tree, the parent insect; or, chemically, by substances known to be generally 
deleterious to that class of animals. 

The fruit being the nidus of the ovum, and the earth the habitat, in which it is 
brought to maturity and makes its abode, and the larva, from its soft and delicate 
structure, incapable of traveling, or sustaining the exposure; when the fruit contain- 
ing the. ^arva has fallen and is rotted and consumed by the insect, the larva must 
descend, by the most direct route, from its original depository, the fruit, into the 
earth, its permanent abode, there to undergo the metamorphoses, which will bring it 
to maturity, and fit it for a new series of depredations, which is so secretly performed, 
that though myriads are employed, they are never detected in executing their work 
of destruction, the deposit of their ova. Hence, I concluded, that one of the most 
effectual preventives, would be paving with brick, stone, shells, or some other hard 
substance, impervious to the soft larva, a circular space round the fruit tree, as 
extensive as the fall of the fruit, by which it would be interrupted in its descent into 
the earth, and consequently perish; or that it might be accomplished, by turning up 
the earth under the tree to the same extent, and thereby exposing to the inclemency 
of the weather, the tender pupa, of which two methods, the former is to be preferred; 
because thereby you arrest the passage of the larva to maturity, and necessarily destroy 
it. The latter method, if not performed in time, may allow the perfection of the imago, 
and in this state it is unquestionably more hardy and capable of providing another 
habitation, as secure and comfortable as that of its first election. And by the experi- 
ments which I have made, its descent and maturity are at uncertain and unequal 
periods, which would make an insuperable difficulty, in point of time, for performing 
the operation; if below the descent, it would necessarily be useless; if after the 
maturity, equally so, for reasons given. 

This view of the subject has led me repeatedly to both experiments, which I have 
fairly and impartially made, without the influence of any prejudice, which it might 
be presumed, my reasoning had connected with or in favor of the former; the result 
was, the fruit with which I made the experiment that had been destroyed by curculi- 
ones, for many years, were in all cases, when I paved or shelled, entirely exempt; in 
two cases only, when the earth under the tree was turned up, at different seasons, the 
fruit escaped injury, but from the number that failed, I was inclined to ascribe these 
two to causes accidental and extrinsic. 

The third method proposed,, viz: to intercept the parent in its ascent of the body of 
the tree, by various obstacles which the mind will readily suggest, and thereby prevent 
its deposit of ova, though I have made no experiments upon it, I conceive to be rational, 
and easily accomplished; and with those species of curculiones, of which there are 
many, whose wings do not admit of flight, but assist them only in climbing, it would 
undoubtedly be effectual. 

The fourth remedy which I propose, of a chemical nature, I have made but partial 
experiments to establish, such as are not yet satisfactory or conclusive; when finished, 
it will give me pleasure to report them, if the result be successful, by a fair and candid 
detail of facts. 

The above seems to be the first definite recommendation for paving 
and the use of various obstacles -to prevent the ascent of the trees by 
the supposedly wingless adults. 
17262°— Bull. 103—12 11 



162 THE PLUM CURCULIO. 

Also during this year (1819) the curculio was first given a scien- 
tific name by an American entomologist, Mr. W. D. Peck, from 
beetles reared from black-knot on cherry; the original account of 
which is given below: 

This insect belongs to the same genus with the Rhynchaenus slrobi or white pine 
weevil, described in the Massachusetts Agricultural Journal for January, 1817, to a 
plate in which I would refer for a representation of the parts of the mouth. In that, 
the rostrum or snout is nearly straight; in the present species it is curved, so as to form 
the segment of a circle. All the thighs have two small obtuse points on the under side. 
In colour it is variegated with white and red hairs; the ground colour of the shelly 
coat on which they are placed is dark brown; The thorax is contracted behind the 
head; its surface is irregular, much pitted, and has a raised longitudinal line in the 
middle, with three small tubercles on each side of it, placed in a triangular form. 
The elytra are marked with longitudinal ridges and on these are placed oblong tubercles 
of which there are ten or twelve; four of these in the middle of the elytra are largest, 
smooth, and of a brown black colour. On the under side the body is pitted, or marked, 
with large impressed points, like the top of a thimble. The first pair of feet is rather 
the largest; the second the smallest, and all sprinkled with white and bright rust- 
coloured hairs. Figure 5 shows the natural size of the insect, and figure 6 magnified. 

Mr. Pomroy was so obliging as to bring me three tumours cut from his plum-trees, 
later in the season, but the larvae had left them. Being, therefore, uncertain whether 
the disease of the plum-trees is to be attributed to this insect or to another species of 
the same genus, I would call it the cherry weevil. It maybe distinguished by the 
specific name of rhychsenus (cerasi) femoribus dentatis; fulvo alboque variegatus, 
elytris tuberculis pluribus carinatis, quatuor in medio manoribus nigris. 

Among the 272 species of this genus, mentioned by Fabricius, there were several 
found in Cayenne and Carolina, which are nearly allied to this; but it differs from 
them all, and appears to be undescribed. 

The evil produced by this insect cannot be wholly remedied; but something may 
be done to diminish the mischief by cutting off the diseased branches. This, how- 
ever, must be done at the right season, and must be the joint care of a whole neighbor- 
hood at the same time. Those which furnished the data above set down, ceased to 
feed on the 6th of July, rose from the earth on the 30th, and were soon ready to deposit 
their eggs in healthy branches; but if the diseased branches be cut off in the last half 
of June, a great number may be destroyed, and most effectually, by burning the 
amputated parts. It is possible, that in some situations they may be disclosed earlier; 
it will therefore be surest to prune away the diseased parts as soon as they appear, 
cleaning the trees now of the old tumours, that new ones may be more readily 
perceived. 

A treatment out of the usual was that followed by a correspondent 
of David Landreth: 

When the fruit is perfectly set or half grown, I take a small hammer and bruise the 
trunk of the tree in 12 or 15 places, from near the root to the branches; the sap or gum 
will run out which I am satisfied will prevent the fruit from falling off. My neighbor, 
Mr. L., has practiced the same with success. I viewed his trees a few hours ago; he is 
well satisfied with the utility of it. 

I will not undertake to give exact reasons why it should prevent the fruit falling 
off at a premature age; it may be that the insects feed on the sap or gum that also there 
may be a superfluous quantity of sap in such trees, I will entirely leave it to those of 
superior judgment. 



REMEDIAL MEASURES: HISTORICAL. 163 

Also, the following in The Farmers' Guide (1824), page 208: 

It is recommended to put a ring round the tree, of a mixture of grease, or blubber, 
mixed with salt. Perhaps some of the other ingredients for destroying worms, would 
answer a better purpose. 

Again, in the New England Farmer, volume 9 (1830), is the follow- 
ing: 

In the month of July, I visited the beautiful settlement of Mr. Rapp, at Economy, 
on the ba T k of the Ohio, 14 miles below Pittsburg, and was highly gratified to see his 
numerous plum and prune trees loaded with fruit, uninjured by the insect. The 
senior Mr. Rapp informed me that while his trees were in bloom, his gardener placed 
around the body of them, a few inches above the ground, two pieces of boards, of suit- 
able size, say six inches by twelve, out of which a semi-circular portion had been cut, 
so that when fitted together, around the tree , they would completely invest the body. 
These were confined together by two narrow battens, secured with screws, on the under 
surface. On the upper surface, a circular channel was cut, half an inch deep, and one 
inch wide, so as to surround the tree. The joints between the two boards, where 
crossed by this channel, were closed with putty, and any vacancies between the boards 
and the tree carefully stopped with clay mortar. The circular channel is then fitted 
with tar, and presents an effectual barrier to the progress of the insects. Some atten- 
tion is required, to see that the tar does not leak out or become hardened. 

An article by James Thatcher, in the New England Farmer for 
March, 1840, is illustrative of a series of recommendations based on 
the believed efficacy of repellent substances, a portion of which is 
given : 

There is another process to be recommended, in which I have great confidence, 
as a part of our warfare against the curculio. It is to make a direct attack upon the 
female beetle while she is about to puncture the fruit to engender her young brood. 
This may be done by throwing from a garden engine or Willis' excellent syringe, a 
liquid substance that will create a sort of deleterious atmosphere which will compel 
her to quit the tree, and will destroy the vitality of her eggs, should they have been 
deposited. I will name the following articles for this purpose: the composition of 
sulfur and lime recommended for grapes in Mr. Kendrick's Orchardist, p. 328; a strong 
decoction of tobacco or snuff; chloride of lime; a weak solution of potash or even 
soapsuds. These materials, if showered over the trees and fruit, would prove so offen- 
sive as to force the female visitor from her generating process. The most proper time 
for this operation is in the evening, in order to meet the enemy, whose attack is sup- 
posed to be during the course of the night. This operation should be repeated sev- 
eral times during the week, from May to August, and the tree should frequently receive 
a thorough shaking, by which the insects will be greatly disturbed and made to fall to 
the ground. Should my plan be deemed too onerous, the cultivator who may adopt 
it in full or even partially, may be assured that (in my opinion) he will have no cause 
to regret his labor. 

Belief in the efficacy of paving is shown by the following article 
which appeared in the New Genesee Farmer, volume 3, page 98 
(1833): 

D. Longstreet says that a gage plum tree which stood over a pavement, ripened its 
fruit in perfection last year, while all the fruit of his other trees of that kind, which 
were not over pavements, was destroyed by the curculio. In order to show that the 
result was caused by the pavement, he says that a plum tree, standing near the path 
to the barn, not paved but which was frequented almost hourly, lost all ita fruit. Such 
facts ought to be recorded and generally known, 



164 THE PLUM CUKCULIO. 

The codling moth and curculio were for a long time confused in 
the minds of many fruit growers and more or less the subject of debate 
in the journals of the day. The following, by N. Darling, from the 
Cultivator, December, 1840, page 190, is illustrative of this fact: 

In the September number of the Cultivator (p. 136) you say in answer to a corre- 
spondent that "the worm in the apple as well as in the plum and cherry is a species 
of curculio." Also, that "the worm with the fruit, falls upon the ground, in which 
the worm takes up its abode in the chrysalis state, until revivified and changed by 
the spring, it issues a perfect insect. 

I am well convinced there is a mistake here, in two particulars: 1st, as to the worm 
in apples being a curculio; 2nd, as to the curculio continuing in the ground till spring. 

In 1831, seeing it stated in all the books that the curculio, in its chrysalis state, 
remained in the ground during winter, I undertook to verify the fact by actual experi- 
ment. The result was communicated to the "New York Farmer" (Vol. IV, p. 178- 
179). But as many of your readers have probably not seen that book, you may do a 
service by publishing an extract from it. 

I put some moist earth into a tumbler, about the first of June and placed about 20 
small peaches, containing worms, upon the earth, and covered the tumbler with a 
piece of glass. June 30th, the worms had all left the peaches and had all crawled into 
the earth below. July the 7th, the worms had divested themselves of their skin, 
without having formed a shell or cocoon, and were nearly changed to bugs. At this 
time they were white, and showed upon the breast the soft rudiments of the proboscis, 
legs, and wings. These parts had not attained their full size, and appeared immovable- 
One insect, however, had completed his metamorphosis and was a perfect bug, of a 
mahogany color. All have since left the earth of their own accord, having finished 
their change, and are now (July 19th) creeping about the tumbler and feeding on a 
plum leaf. On the 10th of July I opened the ground under a peach tree and found 
the insects in great numbers from two to four inches beneath the surface, in all stages 
of their metamorphosis. July 19th, I found one in the earth under an apple tree, but 
could find none under peach trees. It appears then that this insect retreats into the 
earth about the first of June, where it divests itself of its skin, and changes into a bug 
before the 19th of July, by which time it leaves the earth. What becomes of the bug 
from July to May following, remains to be discovered. 

The curculio is not the only insect that produces the worm in our fruits. I stated 
above that about twenty peaches were placed in the tumbler. In the earth under 
them were six small, oval cocoons, thick strong and smoothly spun, which contain 
worms that manifest no approach toward a change. The same cocoons are also found 
under peach trees. The worms in these envelopes are different from those of the cur- 
culio; they are smaller; they are white throughout; 1 while the larvae of the curculio 
have orange colored heads. There is reason for the belief that the larvae of the curcu- 
lio, all or most of them, leave the various fruits in which they are deposited as early 
as the beginning of July, and that the worms found in fruits after that time, have a 
different parent. Some years ago, I preserved a worm from a Vergalieu pear, which 
produced a gray miller. Last November a worm from a Newton Pippin placed itself 
in a cavity on a board, covered itself with a web, and remained till April when it pro- 
duced a gray miller like that produced from the pear. 

I continued my observations during that summer, and sent another communication 
to the New York Farmer (Vol. IV, p. 248), from which the following is an extract: 

I have said there is reason for the belief that the larvae of the curculio, all or most of 
them, leave the various fruits in which they are deposited as early as the beginning of 

1 Probably (Porizon) Thersilochu$ conotracheli Riley, a parasite of the curculio. 



REMEDIAL MEASURES: HISTORICAL. 165 

July, and that the worms found in fruits after that time have a different parent. One 
reason for this belief is, that after that time very little fruit is left in which their eggs 
can be deposited, and what little is left is, for the most part, untouched by the cur- 
culio. Let me present a hasty estimate of cherries, apricots, plums, and peaches, in 
my orchard; on the first of May last, there were probably 200,000; on the first of July, 
the number remaining on the trees did not, I am confident, exceed 500. Of that 500 
perhaps 20, before the middle of August contained a curculio, the rest continued fair. 
I think it would puzzle Dr. Tilton to say where that vast multitude of curculios that 
deposited 199,500 eggs before the first of July, have deposited them since that time, 
if they continue their ravages, .and equally puzzling it must be to devise a reason why 
any fruit has escaped — why only 20 eggs should be deposited, and 480 peaches left 
undisturbec if this vast swarm of insects have continued its operations ever since the 
first of July. It may be said that they resort to apples and pears. But before the 
first of July the greater part of the apples had also disappeared from the trees; most of 
those remaining have continued since untouched by the curculio . The worms found 
in them are not the larvae of that insect. I have not succeeded in finding a curculio 
in a pear at any time. The only worms that I have found in pears, (and I have taken 
pains to collect a considerable number this summer), are the larvae (I believe) of 
the gray miller mentioned in my former communication. They resemble the larvae 
of the curculio in having orange colored heads, but differ from them by being larger, 
and having a slight tinge of scarlet or brick color upon'portions of the body. Instead 
of popping into the ground, they crawl under the rough bark of the trees, inclose 
themselves in a web, and are transformed into a chestnut colored chrysalis. Placed 
in a tumbler with moist earth, they form a web upon the cover of the tumbler, and 
there undergo their change. As none have yet left the chrysalis state, I suppose (as 
was the case with those which I have before preserved) that they do not complete 
their metamorphosis till spring. All the worms found by me in apples, since the 
first of July, have been similar to those in the pear. 

An excellent observer, David Thomas of Cayuga, maintained the prevailing opinion 
in ; egard to the worms in our fruits, and with a view to show that I was incorrect, he 
took "a worm with an orange colored head, from a Bell pear and put it in a tumbler, 
with moist earth, " on the fifth of August. On the eighth of August he took from apples 
"three more worms with orange colored heads, and which appear to be the full grown 
larvae of the curculio — another similar, but only half as long — and two others resembling 
the former with brown heads, but 100 (10?) times less in bulk than the first kind. 
Viewing these last under the microscope, I am satisfied that they also are larvae of the 
common curculio, thus far confirming Dr. Tilton's remark that this insect continues 
its ravages from May until autumn. " (New York Farmer, Vol. IV, p. 205.) 

In a subsequent communication, in October, with his accustomed candor, he says, 
" N. Darling may be interested to learn that the worms which I confined 'with orange 
colored heads,' left the moist earth, and encased themselves in a web under the cover 
of the tumbler. Soon after one of them came forth a dark gray miller; and I conclude 
there was no curculio among them. "We are therefore indebted to him for the interest- 
ing discovery that the larvae of several insects feed on our fruits: and it is now rendered 
at least probable that Dr. Tilton ascribed too much of this mischief to the curculio." 
(New York Farmer, Vol. IV, p. 281.) 

With these facts before us I think we may safely conclude that the worm in apples 
is a larva of a gray miller, and not of the curculio, which is a bug. Also that the curculio 
leaves the ground in a short time after entering it. Its winter retreat has not,- within 
my knowledge, yet been discovered. 

If your correspondent will look under the rough bark of his apple trees in October, 
he will find a great many of the worms from this fruit, which have shut themselves 
in with a web, and are transformed into a chestnut colored chrysalis. If he will care- 



166 THE PLUM CURCULIO. 

fully preserve them, he will find them coming out a gray miller. By simply scratch- 
ing off, or rather picking off this rough bark (the scales or flakes, I mean) a vast multi- 
tude of these insects may be destroyed — not all, however, for they resort to other 
places of concealment, such as crevices in boards, posts and rails. 

That the curculio could be fenced out was the belief of some ; note 
the experience of W. Manice from the Cultivator, of 1854, p. 157: 

W. Manice, of Long Island, constructed many years ago a tight board fence around 
his plum orchard, about nine feet high, with tight board gates. The curculio did not 
fly high enough to enter, many striking the sides of the fence and falling outside. 
An acquaintance when in full fruit informed us that all the trees within the enclosure 
were heavily loaded with plums at the same time he observed a tree outside that had 
lost every specimen. 

The following is interesting as indicating the prevalent opinions of 
fruit growers as to remedies by the middle of the last century: 

At the regular monthly meeting of the St. Louis Horticultural Society, held on the 
7th of May, 1849, the curculio was the subject of some interesting remarks; an abstract 
of which we publish from the minutes. We hope the worthy president will perse- 
vere in his experiments until he shall have discovered a specific for this most serious 
hinderance to the cultivation of fruit. 

The president stated that his attention had been called to the various recommenda- 
tions of remedies or preventives of the ravages of the curculio, one of the most nefari- 
ous pests of the orchard in that part of the country. This insect invariably takes our 
entire crop of apricots, nectarines, and plums, and injures the cherries, and even 
peaches. He has determined to try every practicable proposed remedy of which he 
could avail himself the present season. The following were among those suggested: 

1. Horse stable manure. This was believed to be ineffectual. 

2. Spreading sheets under the trees, and tapping the body and branches with a 
mallet, the insects will fall into the sheets, and may be caught and killed. This is 
believed to be perfectly effectual, though laborious practice: it must be pursued every 
morning for two or three weeks from the time the trees cast their flowers. He presented 
a vial containing sixty-one of these insects, which he caught from three apricot trees 
on the morning of the 5th of April, the young apricots being nearly the size of peas. 

3. Placing a lighted candle under the tree, for two or three hours in the evening in 
a tub or box whitewashed inside, and having at the bottom an inch or two of water. 

4. Placing old iron hoops, or pieces of iron, in the branches of the tree. He had 
seen at his mother's residence, last fall, a green gage tree having an iron hoop entwined 
among its branches, and from which a crop of fruit was always obtained whilst the 

fruit of other plum trees near by, without the iron, was destroyed. Dr. S had 

mentioned to him facts in connection with the subject, which led him to infer that 
some potent effect was attributable to the iron; it may be worthy of a trial. 

5. The insects may be fenced out by a tight board fence eight to ten feet high. A 
gentleman on Long Island succeeds perfectly with his, but he also paves the ground 
and plants his trees in dwarf, six feet apart. 

6. Placing a coat of salt under the trees. This is believed to be ineffectual, as he 
had partly tried it, but without success. 

7. Covering the ground under the trees with clay. This he had tried, and it did 
no good. 

8. Hanging bottles of sweetened water in the trees. 

9. Smoking the trees with the fumes of burnt sulfur. 

10. Washing the trees, and even the fruit with the strongest decoction of tobacco 
and whale oil soap suds will have no effect. 



PREMIUMS FOE REMEDIES. 167 

11. Swine and poultry, running daily among the trees, during the fruit season, as a 
permanent annual practice, will ultimately drive away or destroy the insect. The 
poultry, however, are not alone sufficient. Swine are the best exterminators, by 
destroying the larva? of the insect in the fruit as it falls. The insect will avoid places 
unfavorable to the entrance of its young into the ground. 

Captain Bissell said he had tried horse manure and salt without any effect. He 
was inclined to try the swine. 

General Milburn said that a Mr. Price, of this county, kept off the insects by tying 
a band of sheep's wool around his plum trees. 

Mr. Turner said that a withe around the tree, kept moist with tar, had proved 
ineffectual w.' h him. 

Mr. Clark sard that the insect would not attack the fruit upon a tree standing in a 
frequented walk. 

The foregoing will indicate the general trend of the early remedial 
suggestions. In the literature on the subject there is much testimony 
in favor of pasturing orchards with hogs and sheep, and allowing 
fowls to run in them, and of paving under the trees. Jarring, although 
recommended and practiced to a certain extent by 1830, apparently 
did not come into general use until considerably later. The develop- 
ment of this method forms an interesting chapter in the evolution of 
remedies for the curculio, but may be considered only briefly (p. 168). 

PREMIUMS FOR REMEDIES FOR THE CURCULIO. 

Premiums have often been offered for the discovery of a suitable 
method of control of an injurious insect, and the plum curculio is no 
exception. The amounts of the awards, however, actually offered 
were small as compared with the amounts offered for other species, 
notably the cotton boll weevil, for which a premium of $50,000 was 
offered by the State of Texas. The first suggestion for an award for 
a remedy for the control of the curculio seems to have been made about 
1830. At this time a lady of New Jersey started a movement to raise 
$2,000 by subscription, and the matter was considered by the Penn- 
sylvania, the New York, and the Massachusetts Horticultural Socie- 
ties, the last organization at least recommending that $200 be appro- 
priated by the society for this purpose. 1 The same society, in 1842, 
offered a premium of $100 for a successful remedy for the curculio, 
which amount was raised to $200 by additional subscriptions. There 
were several contestants for this latter premium, though no method 
of control presented particularly warranted the giving of the award. 
A paper highly commended and published in the proceedings of the 
society for 1843 was prepared in this connection by Dr. Joel Burnett. 

As stated in the Genesee Farmer for 1856 (p. 192) a reward of $500 
was offered by the Kentucky Horticultural Society for an effectual 
remedy which would not be so costly and troublesome as to prevent 
its general employment. 

i History Massachusetts Horticultural Society, p. 257. 



168 THE PLUM CURCULIO. 

Ten years later (1865) a gentleman from Philadelphia, writing in 
the Country Gentleman (p. 270), suggested a reward of $50,000 for 
a method of curculio control, though no action appears to have 
resulted from his suggestion. 

A somewhat different plan of securing the subjugation of the cur- 
culio was adopted by the Fruit Growers' Association of Ontario. In 
their list of prizes for 1870 (p. 72) is the following: 

To any person sending to William Saunders, esq., London, transportation prepaid, 
2,000 plum curculio (Conotrachelus nenuphar), the sum of $25, or sending 1,000 the 
sum of $10, or sending 500 the sum of $5. 

As a result of this offer numerous fruit growers made sendings of 
plum curculio during the year, the total reaching 13,653, the largest 
number being sent in by any one person being 2,280, jarred from 20 
plum trees, 10 English cherry, and 30 peach trees, obtained for the 
most part from the plum trees. 

The year following a reward was again offered, but the amount to 
be paid reduced. Thus, for 5,000 curculio, $20; for 3,000, $10; and 
for 2,000, $5. As stated in Mr. Saunders's report to the association for 
1871, the number of beetles received was notably less than during the 
year previous, supposedly on account of the reduction in price, no 
award being made for a less number than 2,000 beetles. 

THE RANSOM CHIP PROCESS. 

Considerable interest was aroused in the so-called Ransom chip 
process proposed by W. B. Ransom, of St. Joseph, Mich., in 1870, the 
discovery of which was announced in an extra of the St. Joseph 
Herald. The proposed method is reviewed at length in the American 
Entomologist for June, 1870 (p. 225), by Dr. Riley, who points out 
that the process had been previously proposed by Mrs. H. Wier, of 
Johnsonville, N. Y., in the Rural New Yorker of January 28, 1865. 
The plan consisted in first taking from under the trees all trash, clear- 
ing and packing the soil for a couple of feet around the collar of the 
tree and, second, in placing pieces of bark, chips, small stones, etc., 
close to the trunk of the tree, for hiding places for the beetles, from 
which they were to be regularly collected and destroyed. 

The method was compared with jarring by Dr. E. S. Hull 1 during 
the period May 29 to June 2, with the result that by the chip process 
13 beetles were taken (including 7 apple curculio), whereas by jarring 
309 were captured. 

JARRING FOR THE CURCULIO. 

Jarring, or shaking, as the practice is very generally designated 
in the earlier literature, was recommended at a very early date. Its 
value rests upon the habit which the beetles have of folding their 
legs and falling to the ground when disturbed. 

i Trans. 111. Hort. Soc, 1870, p. 228. 



JARKISTG FOB THE. CUECULIO. 169 

A suggestion as to the worth of the practice is found in the Bartram- 
Collinson correspondence in 1746 (p. 157). Jarring was more or less 
in vogue at the beginning of the last century. In Dr. Tilton's article, 
published in 1804 (p. 157), he refers to the successful experience in 
jarring of a gentleman living near Baltimore. He also records results 
obtained by Col. T. Forest, of Germantown, who, having a fine plum 
tree near his pump, tied a rope from the tree to the pump handle so 
that the tree was gently agitated every time there was occasion to 
pump water. The consequence was that the fruit on this tree was 
preserved £u the greatest perfection. 

The habit of the curculio to fall to the ground or to play possum 
when disturbed is commented on in the American Farmer for July 17, 
1829, namely: 

When the branch on which it is at work is shaken with some little violence, it drops 
to the earth but makes no attempt to hide. It immediately contracts itself into a 
small lump very much resembling a grain of small black gravel, and thus it evades 
generally the closest inspection. 

Mr. David Thomas was perhaps one of the first fruit growers to 
exploit the method of j arring, and he occasionally published accounts 
of his success, which doubtless greatly hastened its more general 
use. Writing in the New England Farmer for 1831 (p. 413), he says: 

We have lately discovered that much fruit has been punctured by the curculio, and 
we have found it necessary to resort to the method which I proposed in the New York 
Farmer, Vol. Ill, No. 3. By spreading sheets and jarring the trees we have destroyed 
more than 300 of these insects within the last 24 hours, and have only to regret that 
this work has been so long delayed. 

Further along in the article he adds : 

Before closing this comment I wish to express my entire confidence in the method 
which we now employ for destroying this insect; and again recommend it to those 
whose fruit trees stand in inclosures from which geese and pigs must necessarily be 
excluded. Diligent attention to this business night and morning for a short period, 
though it may not destroy the whole colony, will secure a sufficiency of fruit, and 
we ought to remember that the labors of next year may be greatly lessened by gathering 
and destroying in the present season the damaged fruit as it falls. 

An improvement in the method of dislodging the beetles was hit 
upon a year later, as described by Mr. Thomas in the Genesee Farmer 
for 1832 (p. 185). He states: 

Not three days ago I saw that many plums were punctured and began to suspect that 
shaking the trees was not sufficient. Under a tree in the remote part of the fruit 
garden, having spread the sheets, I therefore made the following experiment: On 
shaking it well I caught 5 curculios; on jarring it with the hand I caught 12 more; 
and on striking it with a stone 8 more dropped on the sheets. I was now convinced 
that I had been in an error, and calling in the necessary assistance and using a hammer 
to jar the tree violently, we caught within less than one hour more than 260 of these 
insects 



170 



THE PLUM CTJRCULIO. 



The following spring Mr. Thomas again refers to his method of 
catching the curculio (Genesee Farmer, 1832, pp. 155-156), and 
describes shaking the trees and catching the beetles on sheets kept 
exclusively for the purpose, as commonly practiced. It would thus 
seem that j arring was rather generally employed in his neighborhood 
at that time. 

In 1833 the discovery was made that it was advantageous to 
strike the sawed-ofT butt of a limb as follows : 

This spring I sawed off one or more lateral branches of about an inch in diameter 
from each tree, leaving a stump to project, from which I removed the bark that the 
wood might harden and also made the head convex with a knife to prevent it from 
battering under the mallet. 

There are frequent accounts in subsequent literature dealing with 
the methods of jarring and giving instructions for the preparation 
of sheets (see fig. 34), but the practice seems to have become notably 

general by about 1850. The um- 







W*. — -'WfKsi^-^-- - -. ::'■ --*- 



Fig. 34. — A simple form of curculio catcher for use 
by one person. (After Popular Gardening.) 



brella type of catcher came into 
use apparently somewhat before 
1848. In The Cultivator for that 
year (p. 182) is given a short 
account of an umbrella catcher 
which, it was stated, had been 
employed for some years. Num- 
erous forms of catchers were 
described and some of .them illus- 
trated, but all were essentially of 
the sheet type, to be held or placed 
on the ground under the tree, or in 
the form of an inverted umbrella. 
An interesting resume of Mr. Thomas's experience after more than 20 
years was given by him in The Cultivator for August, 1851 (p. 269), 
in which he expressed fullest confidence in the method and stated 
that whenever the work had been thoroughly done he had never been 
disappointed in results. 

Mr. James Mathews, writing in the Country Gentleman, February 
17, 1853 (p. 102), speaks of having employed the jarring system for 
many years. He employed the umbrella type of catcher. 

A much more pretentious curculio catcher was devised by Dr. E. S. 
Hull, of Alton, 111., a description of which was given in the Practical 
Entomologist for April, 1867, and also in the Iowa Homestead, a 
reduced illustration of which is shown in figure 35. A patent was 
later taken on this catcher by Dr. Hull, but as it proved cumbersome 
several modifications were quickly developed, and some of them by 
Dr. Hull himself. A machine which Dr. Riley considered an im- 



JARRING FOR THE CURCULIO. 



171 



provement over that of Dr. Hull was described in his Third Missouri 
Report, page 20. Dr. Riley stated that this machine, which had been 
devised by Mr. L. M. Ward, was in quite general use around St. 
Joseph and Benton Harbor, Mich. 




Fig. 35.— A cumbersome wheelbarrow type of curculio catcher, developed and patented about 1869. (After 

American Entomologist.) 

Another curculio catcher, devised and patented by Dr. M. M. Hol- 
ton, of Centralia, 111., is also described by Riley. All of these devices 
indicate an increase in the practice of jarring and the general demand 
for apparatus for this purpose. 




Fig. 36.— A light wheelbarrow curculio catcher, for sale as late as 1905. 

At the present time there are perhaps few if any individuals or firms 
offering curculio catchers for sale, although unquestionably a consid- 
erable number are still in use. A form of catcher which was on the 
market in 1905 is shown in figure 36, and has been much used in 



172 THE PLUM CURCULIO. 

western New York. According to the manufacturer, the umbrella 
was made in sizes of 8, 10, and 12 feet, costing from $15 to $16.50, 
according to size. 

Many growers who have jarred for this insect, and especially where 
labor has been abundant, have preferred to use sheets on frames. 
Extensive work has until recently been in progress in the orchards of 
the Hale Georgia Orchard Co. and elsewhere in the South. The 
sheets and mode of use are shown in Plate XIV, figure 2. 

PRESENT STATUS OF JARRING. 

The last few years have witnessed a notable increase in spraying 
for the curculio, with a corresponding decrease in jarring. This old 
remedy will doubtless more and more fall into disuse with the increase 
in spraying operations. 

One of the largest jarring operations recorded is that by Messrs. 
W. M. Scott and W. F. Fiske. 1 During 1900 a Georgia orchardist 
jarred 200,000 bearing peach and 50,000 bearing plum trees about 
six times during the period from April 18 to June 1. Eleven gangs, 
or 55 hands, were engaged in the work, at a total cost of about $1,000. 
It was estimated that about 137,000 curculios were caught during 
the season. Curculio damage in this orchard was placed at about 4 
per cent of the crop, as compared with an estimate of about 40 per 
cent injury in an adjacent orchard of 130,000 trees. 

Although jarring had so long been in use, and was so generally 
recommended, there are practically ho precise data in literature 
indicating just what degree of protection is afforded, nor any rela- 
tive to its value as compared with its cost. 

During 1906, at Myrtle, Ga., an attempt was made to secure data 
on the value of this work on peaches. A block of 1,000 6-year-old 
Elberta trees was selected from a larger block of 10,000 trees and 
jarred every other morning from April 11 to June 9. Twelve trees 
in the jarred block were used for making examinations of the fruit 
throughout the season and an identical number were used in the 
larger, unjarred block of the same variety. The results are shown 
in Table LXXXVI: 

1 Bui. 31, n. S., Bur. Ent., U. S. Dept. Agr., pp. 24-35, 1902. 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate XIV. 




Fig. 1.— A Wheelbarrow Curculio Catcher, Used in New York State. 




Fig. 2.— Curculio Catcher Made by Sheets on Frames, in Use a Few Years 

Ago in Georgia. 



JARRING APPARATUS IN USE OR RECENTLY IN USE AGAINST THE 

PLUM CURCULIO. 



JARRING FOE. THE. CURCULIO. 



173 



Table LXXXVL— Results of jarring Elberta peaches for the plum curculio, Myrtle, 

Ga., 1906. 





Treatment. 


Tree 

No. 


Fruit from ground. 


Fruit from tree. 


Total 
number 
of fruits. 


Total 
number 
of fruits 
infested. 


Average 


Plat No. 


Total 
number. 


Total 
number 
infested. 


Total 
number. 


Total 
number 
infested. 


percent- 
age sound 
fruit. 




Jarred 

Untreated . . 


f 1 

2 

3" 
4 
5 
6 
7 
S 
9 
10 
11 
12 

f 1 
2 
3 
4 
5 
6 
7 
8 
9 

10 
11 

I 12 


75 
43 
56 
72 
43 
113 
35 
96 
43 
19 
24 
6 


24 

29 

7 

29 

10 

20 

12 

19 

12 

2 

7 

1 


79 

58 

96 

157 

192 

•310 

120 

345 

270 

99 

47 

30 


2 

6 

4 

25 

10 

12 

3 

15 

17 

7 

3 

5 


154 
101 
152 
229 
235 
423 
155 
441 
313 
118 
71 
36 


26 
35 
11 
54 
20 
32 
15 
34 
29 

9 
10 

6 
























I 






























625 


172 


1,803 


109 


2,428 


2S1 


88.42 




188 
35 
61 
71 
14 
21 
30 
36 
8 
32 
20 
27 


45 
6 

14 

22 
6 

17 
9 

11 
5 
8 
4 
6 


356 
138 

99 
195 

44 
123 
129 
192 

29 
175 

95 
105 


38 

9 

7 

17 

3 

14 

13 

11 

1 

5 

9 

8 


544 
173 
160 
266 

58 
144 
159 
228 

37 
207 


83 
15 
21 
39 

9 
31 
22 
22 

6 
13 
























II 


















115 13 
132 14 














543 1 153 


1,680 


135 


2,223 


288 


87.04 



As will be noted, the jarred plat gave 88.42 per cent of fruit free 
from infestation, as against 87.04 per cent on the untreated block, a 
difference in favor of the jarred plat of 1.38 per cent. Only 2,606 
beetles were captured during the season, and the comparative 
scarcity of these doubtless explains why there was practically no 
difference between the two blocks. 

Table LXXXVII gives results of jarring peaches at Siloam 
Springs, Ark., during 1908. A block of 950 Elbertas was jarred from 
March 28 to June 27. Nine trees from the jarred block and a like 
number from an adjacent untreated part of the orchard were used 
for making counts, as detailed in the following table. 



174 



THE PLUM CUECULIO. 



Table LXXXVII. —Results of jarring Elberta peaches for the plum curculio, Siloam 

Springs, Ark., 1908. 





Treatment. 


Tree 
No. 


Fruit from 
ground. 


Fruit from 
tree. 


Fruit knocked 
off in j arring. 


Total 
num- 
ber of 
fruits . 


Total 
number 
of fruits 
infested. 


Average 
percent- 
age of 
sound 
fruit. 


Plat 
No. 


Total 
num- 
ber. 


Total 
num- 
ber in- 
fested. 


Total 
num- 
ber. 


Total 
num- 
ber in- 
fested. 


Total 
num- 
ber. 


Total 
num- 
ber in- 
fested. 




Jarred 

Untreated . 


f 1 
2 

3 
4 
5 
6 

7 

8 

. 9 

f 1 
2 
3 

4 
5 
6 
7 
8 
9 


815 
520 
498 
469 
326 
512 
705 
679 
461 


14 
3 
8 

26 
5 
6 

15 

12 
8 


47 
45 
31 
. 22 
26 
19 
83 
31 
33 


IS 

13 

10 

7 

7 

7 

25 

11 

S 


309 
165 
110 
92 
87 
183 
267 
211 
182 


1 
1 



1 





l 




1,171 
730 
639 
583 
439 
714 

1,055 
921 
676 


33 
17 
18 
33 
13 
13 
40 
24 
16 
















I 




















4,985 


97 


337 


106 


1,606 


4 


6,928 


207 


97.01 




324 
352 

341 
513 
458 
598 
243 
480 
414 


28 
29 
23 
39 
22 
35 
32 
22 
22 


32 

29 
25 
49 
34 
42 
37 
40 
41 


17 
13 
11 
24 
15 
19 
17 
12 
13 






356 
381 
366 
562 
492 
640 
280 
520 
455 


45 
42 
34 
63 
37 
54 
49 
34 
35 














:: 












II.... 
















































3,723 


252 


329 


141 






4,052 


393 


90.30 











The spring of 1908 in that locality was cold and the beetles, which 
were not numerous, were much retarded in their movements. A total 
of 2,189 curculios was taken during the season. The jarred block 
shows a gain of only 6.71 per cent of sound fruit over the block not 
jarred. 

Also, at Barnesville, Ga., during 1910, a block of 336 trees in 10 
rows was jarred from March 10 to time of picking fruit (and subse- 
quently for other records). A check plat of 60 trees (10 rows of 6 
trees each) was laid off on one end of the jarred block. Counts of 
fruit for infestation were made on 20 trees of each plat, as shown in 
Table LXXXVIII. A total of 6,994 beetles was captured by July 30, 
when all fruit had been gathered. 



JARKING FOR THE CUECULIO. 



175 



Table LXXXVIII. — Results of jarring ETberta peaches for the plum curculio, Barnes- 

ville, Ga., 1910. 



Plat 
No. 


Treatment. 


Tree 
No. 


Total 
num- 
ber of 
fruit. 


Total 
num- 
ber of 
fruit in- 
fested. 


Aver- 
age per- 
centage 

of 
sound 
fruit. 


Plat 

No. 


Treatment. 


Tree 
No. 


Total 
num- 
ber of 
fruit. 


Total 
num- 
ber of 
fruit in- 
fested. 


Aver- 
age per 
centage 

of 
sound 
fruit. 


1.... 


Jarred 


f 1 
2 
3 

4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
16 
17 
13 
19 
. £0 


857 
1,S45 
1,286 
1,076 
606 
529 
615 
547 
434 
439 
295 
159 
480 
355 
519 
486 
478 
262 
413 
112 


48 

80 

115 

168 

19 

12 

7 

2 

1 



3 

4 

13 

8 

2 

8 

9 

6 

13 

4 




II... 

i 


Untreated... 


( * 

3 

4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
16 
17 
13 
19 
. 20 


961 
1,890 
1,123 
1,238 
364 
491 
410 
675 
470 
637 
184 
726 
421 
706 
398 
256 
424 
178 
633 
368 


286 
299 
137 
147 
46 
95 
48 
49 
48 
54 
18 
59 
65 
80 
79 
42 
61 
64 
57 
35 







11,793 


522 


95.57 


12, 553 


1,769 


85.91 



Comparing the amount of uninfested fruit from the two plats, 
there is shown a gain in favor of jarring of 9.66 per cent of the crop, 
an amount quite insufficient to compensate for the cost of the work. 

During 1909 Mr. W. W. Chase/ of the Georgia State Board of 
Entomology, following a plan outlined by the Bureau of Entomology, 
jarred a block of 1,200 Elberta peach trees. The work of jarring, 
although carried out irregularly on account of scarcity of suitable 
labor, nevertheless gave results of interest. The block of trees 
used was 40 by 30 rows and paralleled a piece of woods, being separ- 
ated only by a farm road. Rows were numbered from 1 to 30, 
beginning with the one parallel to the woods. In the jarred block, 
10 trees were selected for making examinations of all of the fruit 
and 8 trees were selected from a nearby section of the orchard, 
untreated. 

As stated in the table, a total of 4,338 peaches was examined from 
the 10 jarred trees, of which 1,739 were infested, giving a percentage 
of sound fruit of 59.91. From the unjarred block of 8 trees a total 
of 2,515 fruits was taken, 1,664 being infested, giving a percentage 
of sound fruit of 33.84, a difference in favor of jarring of 26.07 per 
cent. 2 



» Bui. 32, Ga. State Bd. Entomology, p. 29, 1910. 

2 In the publication cited an error in computation manifestly exists where a benefit of 6 per cent is 
stated in text, though a loss of 6 per cent is given in the table, while a correct computation from the 
numbers given of infested and uninfested fruit shows a benefit of 26 per cent. 



176 THE PLUM CURCTTLIO. 

Considering the several records of jarring on peach given above, 
it would appear that this practice, on the whole, is not warranted 
from the benefits derived. Notwithstanding the large total of 
beetles caught in the course of the Barnesville experiment, averaging 
20.81 per tree, there was a lessening of infestation of only about 10 
per cent, as compared with the check. In the other instances, 
where the insects were less abundant, the difference is inconsequential. 

It is, however, a firmly established belief that jarring has been of 
the greatest value in protecting the plum crop, though no exact 
data have been given, and the inference possibly follows the fact of 
capture of the beetles in considerable numbers. It is regretted 
that there has been no opportunity to try jarring on plums. In 
jarring for peaches, furthermore, quite a number of the fruit is 
almost unavoidably knocked off, a considerable proportion of which 
is sound. When there is an abundance or excess of fruit, this is 
beneficial; but when the crop is light, there is an important loss 
of fruit. In the Siloam Springs work, in 1908, a total of 1,610 peaches 
was knocked off during the season from the 9 trees, of which 4 only 
were infested. 

CULTIVATION FOR DESTRUCTION OF PUP.E. 

As has been shown elsewhere (p. 87), practically all of the larvae 
of the plum curculio pupate less than 3 inches below the surface of the 
soil. Over 92 per cent pupate within 2 inches and 63 per cent within 1 
inch of the surface of the ground. The pupse of the curculio, in com- 
mon with those of many other insects, are extremely tender and are 
readily killed or injured by disturbance of the soil. It is probable 
that the mere breaking of the pupal cell, leaving the earth in contact 
with the body of the pupa, would be fatal to many, while others are 
undoubtedly killed by the crushing action of the earth. Superficial 
tillage of orchards when the pupse are in the ground in maximum 
numbers should therefore serve greatly to reduce their number for the 
following season, and tillage during this season is extremely desirable 
as a part of proper orchard management. Pupae not actually killed 
are exposed to the elements and are subject to the attacks of preda- 
ceous enemies, as ants, bird, etc. Sunlight appears to be quickly 
fatal to them and, as stated by Crandall, exposure to the air on a 
warm day in the shade will result in their death in a few hours. 
Extended observations on the life history of the curculio from various 
localities (p. 64) indicate that the insect is in the pupal condition in 
the ground for any locality in from 50 to 65 days after the falling of 
the blossoms of such fruit as the peach and plum. Data have also 
been presented to show that the minimum time spent in the 
ground is about 20 days, though the actual period of pupation is less. 



CULTIVATION FOE DESTRUCTION OF PUP.E. 177 

Shallow cultivation should begin therefore in about 9 weeks after 
blossoming of peach. These cultivations should be frequent, that is, 
every week or oftener if practicable, and continued for 6 or 7 weeks. 
As most of the larvae enter the soil near the deserted fruit, the earth 
under the spread of the limbs of the trees will contain the great ma- 
jority of the pupae and should receive special attention in the course 
of the cultivations. 

Some experiments have been made to determine the effect, on pupae, 
of disturbing the soil. Boxes containing soil were kept in a way to 
approximate out-of-doors conditions as nearly as possible. In some 
boxes the soil was stirred, and in others left undisturbed for com- 
parison. While it has been impossible exactly to duplicate the dis- 
turbance of the earth that would result from field cultivations, yet 
the results are in a way comparable, and indicate as definitely, perhaps, 
as may be determined what may be expected from work of this char- 
acter. The essential features of the results are shown in Table 
LXXXIX. 

In the work at North East, Pa., the boxes were sunk in the soil 
beneath peach trees so that the top would be about level with the 
surface, and were thus subjected to practically normal conditions. 
As indicated in the table, the soil in two boxes was disturbed with a 
rake on July 11 and 20, while two other boxes were left undisturbed. 

In the experiments at Siloam Springs, Ark., in 1908, boxes 2 feet 
square without bottoms were sunk practically level with the earth 
under the shade of an apple tree. One box was cultivated with a hoe 
June 23. 

In the tests in the insectary at Washington, D. C, in 1908, 4 lots 
were used, 2 being treated and 2 untreated. The larvae were placed in 
boxes 24 by 10 inches and 8 to 10 inches deep. These were sunk 
almost level with the surface of the earth. Lot No. 1 was cultivated 
by means of a hoe July 8 and 15, while lot No. 2 was cultivated only 
once, on July 15. The soil was disturbed to a depth of 6 inches, 
exposing many of the pupae. 

At Douglas, Mich., the boxes were placed in a bright though some- 
what shaded location and the soil in lot No. 1 was disturbed weekly 
by means of a small stick or lead pencil drawn back and forth, extend- 
ing to a depth of 3 or 4 inches in the soil. 

In the experiments at Barnesville, Ga., in 1910, 4 bottomless 
wooden boxes 10 by 12 by 8 inches were used and sunk in the soil on 
the north side of a house, thus being shaded for about one-half of the 
day. Lots Nos. 1 and 3 were placed in sandy loam and lots Nos. 2 
and 4. in red clay. 

17262°— Bull. 103—12 12 



178 THE PLUM CURCULIO. 

Table LXXXIX. — Effect of stirring soil on destruction of pupae of the plum curculio. 



Locality and date. 


Lot 
No. 


Num- 
ber of 
larvse 
used. 


Treatment given soil. 


Adults 
emerg- 
ing. 


Per- 
centage 

of 
adults 

from 
larvae. 


Aver- 
age 
per- 
centage 
adults 
from 
treated 
boxes. 


Aver- 
age 
per- 
centage 
adults 
from 
un- 
treated 
boxes. 


Per- 
centage 
gain 
from 
treat- 
ment. 


1906. 
North East, Pa 


1 

2 
3 

4 

1 
2 
1 

2 
3 

4 

1 

2 
1 
2 
3 
4 


200 

200 
200 
200 

451 
451 
558 

51 

468 
137 

98 

98 

173 
191 
173 
191 


Soil disturbed July 11 

and 20. 
do 


25 

32 
71 

75 

60 
135 
20 

24 

267 

59 

2 

17 
21 
12 
119 
98 


12.50 

16.00 
35.50 
37.50 

13.30 
29.93 
3.58 

47.06 
57.05 
43.07 

2.04 

17.35 
12.14 
6.28 
68.79 
51.31 








Do 


14.25 






Do 


Soil not disturbed 

do 






Do 


13.30 


36.50 


22.25 


1908. 
Siloam Springs, Ark 


Soil disturbed June 23.. . 

Soil not disturbed 

Soil disturbed July 8 

and 15. 
Soil disturbed July 15. . . 

Soil not disturbed". 

do 




Do 


29.93 


16.63 


Washington, D. C 




Do 


7.22 






Do 






Do 


2.04 


53.88 


46.66 


1910. 


Soil disturbed f r e - 
quently. 

Soil not disturbed 

Soil disturbed June 17.. . 

Soil disturbed June 8 

Soil not disturbed 

do 




Do 


17.35 


15.31 






Do 


9.06 






Do 






Do 




59.61 


50.55 










10.20 


43.85 


33.65 

















As will be noted, there is with one exception an important decrease 
in the number of adult curculios emerging from boxes in which the 
earth was stirred. In the case of lot No. 2, at Washington, D. C, 
an unusually large number of adults emerged. The larvse were 
placed in this box June 29 and were doubtless all in the pupal stage 
by July 15, when the cultivation was given. It is to be noted, how- 
ever, that there is a considerable variation in the percentage of insects 
killed by stirring the soil from the different localities. This perhaps 
results from differences in the methods of treatment. The total 
average percentage of adults emerging from the treated boxes, 
namely, 10.20, as compared with the total average from all untreated 
boxes, namely, 43.85, shows a difference in favor of stirring the soil 
of 33.65 per cent. Comparing the total number of beetles emerging 
from the untreated boxes, 841, with the total number of beetles 
from the treated, 196, shows a probable number killed by treatment 
of 645, a percentage of benefit of 76.75. 

SPRAYING WITH ARSENTCALS. 

It is impossible to state with certainty who first used arsenical 
poisons for the control of the plum curculio. They doubtless came 
in along with the use of Paris green against cankerworms and the 
codling moth. Paris green was recommended by Mr. G. M. Smith, 



SPKAYING WITH ARSEISTICALS. 179 

of Berlin, Wis., to the St. Joseph, Mich., Horticultural Society in the 
fall of 1870/ in the article which follows, which is the earliest recom- 
mendation we have seen: 

My method of destroying the little Turk is to give the trees a judicious sprinkling 
of Paris green. My plum trees are living witnesses of the excellence of this treatment, 
for they are for the first time loaded with fruit and some of them overloaded, and not 
a mark of the curculio can be found. This is the third season in this region that we 
have used the Paris green for destroying the Colorado potato beetle, and I find it 
effectual not only for them, but for all insects that feed on the foliage of trees or plants. 
No other preparation, as I am aware, has yet been used that is so inexpensive and 
easily prepared and applied as this. It is a perfect protection to the melon and squash 
vines against the ravages of the striped bug, to rose bushes from the slug, and the 
currant and raspberry from the worm. This is as far as my experience extends, but 
I see no reason why the cankerworm and the caterpillar could not be destroyed by 
this preparation. Last season I applied the Paris green to my trees, and I was satisfied 
that it had its effect on the curculio, but the season was so cold and wet here, and 
insects generally were so scarce and the fruits rotted so badly, I could not fully decide. 
But this season the unusual warm weather brought them out early, and on noticing 
their marks on the fruit I made an application of the green to my trees and repeated 
it every week or ten days. The fruit that was stung dropped off, but it is the last I 
have seen of the curculio, although in other localities where it has not been used they 
have been constantly at work. My manner of using this poison is to mix 30 parts 
of flour or fine middlings to one of the Paris green (this is the same proportion that we 
use on our potato vines) ; take a two or three quart tin pail and perforate the bottom 
and fasten to a pole, and while the dew is on shake it over the tree, standing on the 
windward side and not inhale any of the dust. A slight dusting is sufficient, and it 
will be found strong enough for all practical purposes. 

The value of Paris green for this insect was questioned by Dr. 
Riley in the American Entomologist and Botanist for October, 1870, 
and the paragraph which appeared there also appeared in his Third 
Missouri Report, published the same year. Riley states: 

Even if the uniform application of such a poisonous drug on large trees were true, 
it would never succeed in killing one curculio in a hundred. Paris green kills the 
leaf-eating beetles by being taken internally with the larvae, but the curculio, with 
its snout', prefers to gouge under the skin of the fruit, and only exceptionally devours 
the leaves. Yet, notwithstanding the palpable absurdity of the remedy it is very 
generally passed from one journal to another without comment. 

It would seem that the suggestion by Mr. Smith in 1870 was very 
generally copied in the horticultural and agricultural journals of the 
day. The writers, however, have not been able to find references to 
the subject during the interim from 1870 to about 1880. The recom- 
mendation had apparently not made much impression, for in an 
extended article on the plum curculio, dealing especially with reme- 
dies, Mr. B. Gott, in the Annual Report of the Entomological Society 
of Ontario (1879), makes no mention whatever of Paris green or 
other arsenicals. 

1 Moore's Rural New Yorker, vol. 22, p. 45, 1870. 



180 THE PLUM CURCULIO. 

By the early eighties, however, Paris green had come into some 
use. Thus Riley and Howard record the case of Mr. J. Luther 
Bowers, of Herndon, Va., who had informed these gentlemen that 
during the summer of 1880, while he was living in Clark County, 
Va., he had sprayed his trees with Paris green in the proportion of 
1 tablespoonful of green to 5 gallons of water, making the applica- 
tion with a Whitman fountain pump. He sprayed soon after the 
petals fell and again in a week or ten days. The result was the most 
perfect crop of plums he had ever grown. 

In his annual address as president of the Ontario Entomological 
Society, delivered October 15, 1884, Mr. William Saunders, con- 
cerning the Paris green treatment for the curculio, said: 

From the evidence thus far obtained it would appear that the remedy which has 
been found so efficacious in subduing the codling moth of apple, namely, Paris green 
and water in the proportion of a tablespoonful of the poison to a pail of water, will also 
protect the plum crop from the ravages of the curculio. 

Under the caption "Paris green and the curculio, " Mr. William 
Creed, writing in Purdy's Fruit Recorder for November, 1885, states: 

In the October number of the Fruit Recorder of the present year, you invite the 
experience of those who have experimented with Paris green upon the curculio. You 
will find a record of facts in this direction, from my pen, in your paper dated August, 
1884, and until some tangible refutation can be produced by others to affect its value, 
it should not be looked upon with distrust. That Paris green will " do the buisness " 
for the little Turk, I think is irrefutable — certainly it is so from my own knowledge 
and trial for the three last seasons, and I will say positively that on very close inves- 
tigation upon this year's crop, I have not had one plum, prune, or damson fall from 
the punctures of a curculio. But previous to the use of this remedy I looked upon 
plum culture with an instinctive dismay almost ungovernable, on account of its non- 
reliability. Of course, it is not for me to force an argument or intrude too much upon 
your columns concerning this curculio remedy, but will simply crave a little space to 
show the sample of some plum growers' logic when told of my experiments and re- 
sults. The whole batch of arguments by these men do not, however, amount to a 
"row cf pins." The following "walks and talks" happened in 1884. The first was 
with a nurseryman, who said, so far as 1884 was concerned, he considered the apparent 
success as stated was no criterion to go by, as it was a great plum year in this neighbor- 
hood. The second talk was with a gentleman who has about 5 acre3 of plums, 
prunes, and damsons. He would not listen to the subject a moment. " But, " said I, 
"you now have coming into bearing a fine lot of nectarine trees and you may want a 
curculio remedy, " and I at once suggested the intelligent use of Paris green by spray- 
ing, but to no avail. " Shaking, " would do for him. The third gent was from Michi- 
gan and editor and proprietor of a paper and a lover of good fruits, but hater of the 
curculio, which was evidenced by saying that his remedy for the curculio was to cut 
the tree down, which he had done, and bought his plums from distant localities where 
the insect is less plentiful and the plum crop more to be depended upon. 

You will see from the foregoing that there is but poor encouragement and little 
temptation to introduce a good thing, and had you not invited another year's expe- 
rience, I should have let the matter drop. Let it be understood that I do not claim 
priority of suggestion of the use of Paris green for the extinction of the curculio, as 
there may have been thousands of others investigating the matter on the same basis 
and about which I am totally ignorant; but what I do know is that I gave you my 



SPKAYING WITH AKSENICALS. 181 

method after a second year's trial, and as in this case, so also with regard to pear blight, 
I first put forth my theory of the latter in the Fruit Recorder, as being among the papers 
with the largest circulation and as most likely to meet with the largest results and atten- 
tion; and in November, 1877, when I classified pear blight as a zymotic disease and 
suggested an investigation upon this theory it was apparently at once taken up by 
Prof. Burrill and continued by other professors of microbotany, and to-day the 
bacterian theory of pear blight has become an established fact and the prevention or 
modification of the disease may be looked upon with a degree of certainty at no distant 
day. Now for some one to step forward and supplant the first stepping-stcne to the 
proper study of pear blight as it appeared in the Recorder of 1877. 

In the spring of 1885, Dr. Riley, in an address before the Missis- 
sippi Valley Horticultural Society, at New Orlenas, La., discussing 
the feeding habits of the beetles, urged experimentation with arseni- 
cals in tins direction, as promising fair results — not, however, in the 
very nature of the case as satisfactory as in the case of the codling 
moth. 

During the summer of the same year Dr. S. A. Forbes began ex- 
periments in Illinois in the control of the codling moth and apple 
and plum curculio, reporting the results in the Prairie Farmer of 
December 19, 1885, and also in the Transactions of the Illinois State 
Horticultural Society for that year, which appeared from the press 
the following year. Paris green and London purple were tried on 
apple. Paris green was used at the rate of three-fourths ounce to 
2\ gallons of water (equaling approximately 1 pound to 50 gallons), 
the metallic arsenic present being 15.4 per cent. Two trees were 
sprayed eight times during the season, the first applications being 
made on June 9 and 13, respectively. Two trees of the same variety 
of apple were left unsprayed for purposes of comparison. 

In regard to the effect of the treatment of the curculio, Prof. 

Forbes says: 

Of the 1,975 apples from these two poisoned trees which were examined for the 
curculio injury, 542, or 27.3 per cent, bore the brand of the insect's beak, while of the 
1,172 obtained from the check trees, 602, or 57.3 per cent, had been so injured, the 
ratio of apples punctured by the curculio on the poisoned trees being half as many 
times on the trees that had not been sprayed. A careful inspection of our tables 
showed that this was a fact apparent throughout the season. Considering the picked 
apples only the results are somewhat more favorable, and if the fallen apples are also 
taken into count, the percentage of those damaged by the curculios on the check trees 
being 76.5 and upon those sprayed with Paris green 34.4 per cent. 

During the summer of 1886 Prof. Forbes continued his experiments 
with arsenicals in the control of the codling moth, particularly com- 
paring Paris green and white arsenic, noting also the effect of the 
treatments on the curculio. 

These experiments by Prof. Forbes seem to be the first careful 
ones made to determine the value of arsenicals in curculio control. 
In an earlier part of his article Prof. Forbes notes that Paris green 
had been very generally recommended. 



182 THE PLUM CURCULIO. 

In the report of the secretary of the State Board of Agriculture for 
Michigan for 1887, Prof. A. J. Cook reports upon Paris green for the 
curculio as follows: 

Paris green in the proportion of 1 tablespoonful to 6 gallons of water was very thor- 
oughly sprayed upon 4 plum trees May 18. The petals had all fallen, but the dried 
calyces still clung to the fruit. On August 20 the trees were visited, when it was 
found that the two treated trees of the wild goose variety had dropped all their fruit, 
as had the untreated trees of the same kind. Another treated tree of a yellow variety 
was loaded with plums, of which only 15 per cent were stung and those not badly. 
The fourth treated tree was a purple variety and had not less than 75 per cent of its 
fruit badly stung. 

During the season of 1887 experiments were begun with Paris green 
sprays by Prof. W. B. Alwood, at that time an agent of the Division 
of Entomology of this department, as detailed in the Report of the 
Entomologist for that year. These experiments were not begun 
until after the beetles had commenced work. No definite inferences 
in regard to the experiments may be drawn, since these were not 
finally concluded. Prof. Alwood thought, however, that the cur- 
culios ate enough to make it possible to poison some of them, but the 
benefit derived was in his opinion yet unsettled. 

In Bulletin 3 of the Ohio Agricultural Experiment Station, issued in 
May, 1888, Prof. C. M. Weed, under the caption " Experiments with 
remedies for the plum curculio," announced proposed tests of three 
specified methods of control of this insect, and adds: 

Spraying with London purple or Paris green as soon as the blossoms fall as recom- 
mended for the apple. I am reliably informed by many of the largest fruit-growing 
firms of western New York that in this way they succeeded in avoiding the curculio 
and raised large crops of plums. The method has been recommended at various times 
for several years, but as yet has certainly received little attention. 

The same season Prof. Weed put into effect his line of treatment, 
the results of which were given in Bulletin 4 of the Ohio Station, 
which appeared in July. A young orchard of early Richmond cher- 
ries was employed, and in regard to his work he concluded as follows : 

(1) That three-fourths of the cherries liable to injury by the plum curculio can be 
saved by two or three applications of London purple in a water spray (in the propor- 
tion of 1 ounce to 5 gallons of water) made soon after the blossoms fall. (2) That if 
an interval of a month occurs between the last application and the ripening of the 
fruit no danger to health need be apprehended from its use. As a precautionary 
measure, however, I would advise in all cases, and especially where there are few 
rains during this interval, that the fruit be thoroughly washed before it is used. 

Prof. Weed continued his studies of spraying for the curculio in 
1889, using also the early Richmond cherry. His statement of 
results covering two seasons' work on cherry is as follows: 

This series of experiments carried on through two seasons upon two varieties of cherry 
trees and four varieties of plum trees, during which a total of 6,500 cherries have been 
individually examined, seems to me to confirm the conclusions provisionally an- 
nounced one year ago, which may now be put in the following form: (1) That about 



SPRAYING WITH ARSENICALS. 183 

three-fourths of the cherries liable to injury by the ourculio can be saved by two or 
three applications of London purple in a water spray in the proportion of 1 ounce to 
10 gallons of water. (2) That a sufficiently large proportion of the plum crop can be 
saved by the same treatment to insure a good yield when a fair amount of the fruit 
is set. (3) That if an interval of a month or more occurs between the last application 
and the ripening of the fruit no danger to health need be apprehended from its use. 
(4) That spraying with the arsenicals is cheaper and more practical than any other 
known method in preventing the injuries from this insect. 

During the season of 1890 spraying experiments on a commercial 
scale were carried out. by Mr. Weed in an orchard of 900 five-year-old 
plum trees in the fruit belt along the lake shore in northern Ohio, 
and a comparison was made relative to the merits of spraying versus 
jarring. As a result of this test several plum orchards in northern 
Ohio were sprayed for the curculio during 1891 and the consensus 
of opinion of the growers was in favor of the practice. Tests were 
also made the same season by the horticulturist of the Ohio Station, 
Prof. W. J. Green, both on the station grounds and in Ontario County, 
Ohio. Paris green was used in combination with Bordeaux mixture. 
The results on sprayed trees showed that about 20 per cent were 
injured by the insect, whereas unsprayed trees had about 70 per cent 
of injured fruit. 

Prof. Herbert Osborn, at that time an agent of the Division of 
Entomology of this department, also carried out spraying experi- 
ments in the use of arsenicals against the curculio during the summer 
of 1888. The poison used was London purple, at the rate of one-half 
pound to 100 gallons of water, with the addition of a small amount of 
soapsuds. The first treatment was given June 1, when the fruit was 
the size of small peas and before any indications of injury by the 
insect were to be found. The results of counts of all fruit from sev- 
eral varieties treated, sprayed and unsprayed, gave for the sprayed 
trees 32.48 per cent stung and 5.71 per cent containing larvae. The 
unsprayed trees gave 41.86 per cent stung and 10.39 per cent of the 
fruit infested. It was concluded that the proportion of fruit stung in 
the. orchard was so small as to give no benefit from spraying. 

London purple was also tested during the season of 1888 on plums 
by Mr. G. C. Brackett, at Lawrence, Kans. Prof. Cook, in Bulletin 
39 of the Michigan Agricultural Experiment Station, issued in 1888, 
says: 

It will be remembered that I have used the London purple several years with quite 
indifferent success to keep out principally the curculio. The fact that some fruit 
growers reported excellent success with this remedy led me to conclude that possibly 
I had not been persistent and thorough enough in this warfare. The curculio com- 
mences to work anywhere on the plum, which has a smooth surface, while the codling 
moth lays its egg right in the cup or funnel-like calyx end of the apple. Thus the 
wind and rain would free the plum or cherry or general surface of the apple of the 
poison much more readily and quickly than they would the rough cavity end of the 
apple. Thus we can understand how, granting that the arsenites are alike effective 



184 THE PLUM CURCULIO. 

against the codling moth and curculio, more care would be required in resisting the 
attack of the latter. This season we arranged our experiments with this point directly 
in view. On June 4, the trees, both plum and cherry, were jarred and curculio were 
caught. The mark of the curculio was also found on both cherries and plums. The 
trees were sprayed June 6, June 12, and June 20. The material was the same as that 
used in spraying the apples, namely, 1 pound London purple to 100 gallons water. 
Careful examinations June 12 found no stung cherries and very few plums. June 26, 
250 cherries were picked from the sprayed trees, and not one was injured. The crop 
of cherries was large and no cherries from the sprayed trees were wormy. July 16 and 
18 the fallen plums were all gathered under the trees and cut open. On tree No. 1 
there were 16 plums, of which 10 were wormy. Tree No. 2 (wild goose), 117 plums, 
23 wormy. Tree No. 3 (Washington), 33 plums, 3 wormy. Close examination found 
no stung plums on the trees, and the crop upon picking was very free from injury. 
Cherry and apple trees near by not sprayed suffered seriously. 

CONCLUSIONS. 

From these experiments and those of former years I conclude that while one appli- 
cation will not save our plums and cherries and prevent apples from being stung, 
two or three applications may be of signal advantage. 

In 1888 Prof. Forbes began a series of observations to determine 
some details of the food and feeding habits of the curculio and to test 
its susceptibility to arsenical poisons when distributed on the trees 
frequented. Observations were also made on a strength of poison 
which might be used on peach foliage without marked injury. As a 
result of his studies he concluded: 

There can certainly be no further question of the liability of the curculio to poisoning 
by very moderate amounts of either London purple or Paris green while feeding on 
the leaves and fruit of peach and plum, but much additional experimentation is 
needed to test the possibility of preventing serious injury to these fruits by this means. 
The pupal hibernation and late appearance of a considerable percentage of the cur- 
culios make it possible that spraying must be several times repeated and perhaps car- 
ried further into the season than is consistent with safety; and the limit of tolerance of 
these poisons by the peach under ordinarily trying circumstances had not been clearly 
ascertained. Further, the observations reported above on the food plants of the cur- 
culio make it likely that in nature a smaller proportion of the food of these beetles 
comes from the peach or plum than has hitherto seemed possible, and that poisons 
there applied would kill less certainly. It seems worth while to make the attempt to 
attract the adult to flowering plants in the orchard other than the peach, with the 
hope of poisoning it there (especially late in the season) without using these dangerous 
insecticides on fruits afterwards to be eaten. 

Prof. C. P. Gillette, in Bulletin 9 of the Iowa Agricultural Experi- 
ment Station, issued in May, 1890, records observations on the cur- 
culio and plum gouger, giving results of spraying plums with London 
purple for the control of both of these insects. His work led him to 
believe as follows regarding the efficiency of arsenicals: 

The two applications of London purple and water, although not made at the times 
best suited to destroy the curculio, apparently gave a protection of 44 per cent against 
the ravages of this insect. 



FEEDING EXPERIMENTS WITH POISONS. 185 

London purple and water in the proportion of 1 pound to 120 gallons is much too 
strong a mixture for plum trees. One-half of this strength is as strong a mixture as 
should be used. 

In summing up the situation as to the use of arsenicals against the 
curculio, in 1887, Riley and Howard state: 

On the whole, the remedy is one which is a desirable addition to our list, although 
it will never become so great a success as the application of the poisons for the codling 
moth, and for two reasons: (1) The egg is deposited and the beetle gnaws preferably 
upon the smooth cheek of the fruit where the poison does not readily adhere and from 
which it is more easily washed off; (2) the larva eating directly from the flap does not 
come in contact with the poison as does the larva of the codling moth. 

The foregoing will give a fair idea of the rise of spraying with arsen- 
icals for the curculio. By about 1890 the practice unquestionably 
had become rather general, although jarring was still employed by 
many growers. The injury to the foliage of stone fruits by such 
arsenicals as Paris green and London purple, frequently noted by 
orchardists and the early experimenters, no doubt greatly retarded 
the adoption of these poisons. The development, however, in 1892, 
by the Massachusetts Gipsy Moth Commission, of arsenate of lead, an 
insecticide much less caustic to the foliage than either Paris green or 
London purple, gave a considerable impetus to spraying for the cur- 
culio, especially on peaches and plums. Spraying, however, had been 
in effect two decades or more before its real merits on a commercial 
basis had been determined. The careful experiments of Forbes, 
Weed, Alwood, and perhaps others, had shown unmistakably that the 
injuries could be materially reduced by frequent spraying, and the 
testimony of many fruit growers was decidedly in favor of it. There 
were others, however, who doubted its efficiency, and continued the 
practice of jarring. 

FEEDING EXPERIMENTS WITH POISONS. 

The point has several times been raised in the case of arsenate of 
lead whether this did not act mainly as a repellent; and in an exper- ' 
iment by W. W. Chase a report bearing on this question is given. 1 
A single small peach tree was covered with fine wire screen. The 
tree was literally soaked with lead arsenate, 3 pounds to 50 gallons 
of water, and after the poison had dried another application was 
given. The day following, May 11,372 curculios which had been con- 
fined 48 hours without food were liberated in the cage. Subsequent 
close observation failed to discover a single beetle feeding on the tree, 
and in fact the beetles seemed to have the strongest aversion to it. 
At the end of 10 days all the beetles were dead, except a few which 
may have escaped. It would appear to the writers that in this case 

1 Bui. 32, Georgia State Board Entomology, p. 27. 



186 



THE PLUM CURCULIO. 



the poison was applied much too freely, and as used would undoubt- 
edly have acted as a repellent. In the case of Paris-green sprays in 
water there could be no repellent action attributed, and with arsenate 
of lead, as used in practice, it would seem established that its value 
lies more in killing of the insects than in possible repellent action. 

In the course of these studies numerous feeding tests have been 
made with the curculio, especially with different brands of arsenate 
of lead and other miscellaneous arsenicals. Results of a feeding test 
made in 1906 are shown below (Table XC), where apple, pear, peach, 
plum, and cherry branches bearing foliage and fruit were used. 
Twigs of plants placed in bottles with water were used and all were 
sprayed at some time with arsenate of lead at the rate of 2 pounds 
to 50 gallons of water, using a hand pump and Vermorel nozzle. 
With each fruit the poison test was made in duplicate with a single 
check. After the spray had dried on the foliage the branch was 
placed under a large cylinder with cloth over top, and 20 beetles, 
collected that morning by jarring, were added. 

Table XC. — Tests of the killing effect of arsenate of lead on the plum curculio on 
specified fruits, Washington, D. C, 1906. 





Apple. 


Pear. 


Peach. 


Plum. 


Cherry. 


Dates of examination. 


T3 
CD • 

%6 

Ph 


T3 
CO O 

oZ 
Pn 


ft CD 

-w a 
o o 


T3 
CD • 

CO o 

;?* 

Ph 


§CN 

Ph 


ft CD 

« a 

o o 


CD ■ 

u 

Ph 


T3 

CD • 
flt N 

° ~ 
co O 

Ph 


ft§ 
o o 


T3 

CD • 

Ph 


CD * 
fl CN 

CO O 

Ph 


ft cD 

o o 
20" 


t3 

CD ■ 
gd 

oZ 
Ph 

2 
4 

7 
4 

17 
3 


T3 

ll 

Ph 

1 

4 

7 
5 

17 
3 


ft CD 

-^ a 
o o 
£ ffl 




6 
4 
4 
2 

16 
4 


10 
2 
2 
2 

16 
4 


.... 

1 

19 


4 
3 
6 
6 

19 
1 


2 
6 
6 
2 

16 
4 


"i" 

2 


1 
2 
10 

13 

7 


4 
4 
5 
4 


"i" 
1 

19 


4 
5 
3 
5 

17 
3 


6 
3 
3 
1 

13 

7 


1 


26 


.... 


27 




28 


1 






Total 


3 

17 


17 
3 


2 


Beetles alive at close of observations. . 


18 



The results uniformly show a prompt killing effect on the beetles 
by the arsenate of lead on the varieties of fruits used. It is also 
evident that the insects feed freely during midsummer. 

During 1910, in Georgia, numerous feeding tests were made using 
several of the more important brands of arsenate of lead, as well as 
other miscellaneous arsenicals. In Table XCI are given results of 
feeding tests on peach twigs taken from trees in orchards immediately 
after spraying, April 13 and 14, and placed under cylinders. April 
16, 50 beetles were added to each cylinder and records made daily 
of the number of beetles dying. The poisons were used of the strength 
indicated in the foliage test experiments (p. 205). The killing effect 
of all of the poisons was fairly prompt, the various brands of arsenate 
of lead working fairly uniformly. Red arsenic sulphid and arsenic 
tersulphid were quicker in action than the lead arsenates, although, as 
elsewhere noted, these poisons were notably injurious to the foliage of 



FEEDING EXPERIMENTS WITH POISONS. 



187 



peach. Ferrous arsenate was much slower in action, but effective, 
as shown by comparison of the condition of beetles fed on poisoned 
foliage with the condition of the beetles on the check. 

Table XCI. — Tests of hilling effect of lead arsenates and other arsenicals on the plum 
curculio on peach, Georgia, 1910. 





Beetles dying from each of the arsenicals. 


Dates of 
death of 


Check 

not 
sprayed. 


Arsenate of lead. 


Pow- 
dered 
arse- 
nate 
of 
lead. 


Fer- 
rous 
arse- 
nate. 


Red 
arse- 
nic 
sul- 
phid. 


Arse- 
nic 
ter- 
sul- 
phid. 


Arse- 


beetle. 


No. 1. 


No. 2. 


No. 3. 


No. 4. 


No. 5. 


No. 6. 


No. 7. 


No. 8. 


ter- 

sul- 

phid.i 




























3 
17 
16 
1 
4 
5 
2 
1 




18 




4 
2 
8 
9 
7 
8 
2 
3 
3 
2 
1 


1 
3 
5 

12 
6 

13 
2 
1 
2 
2 
1 
1 


4 

7 
5 
8 
8 
5 
3 


4 
1 
5 

6 
10 
7 
8 
5 
1 


8 
5 
3 
4 
9 
5 
7 
4 
2 


4 
7 
2 
6 
5 
10 
3 
6 
1 


4 
8 
3 

11 
6 

10 
1 
3 
2 


4 
16 
7 
4 
4 
7 
5 
1 
2 


5 
1 
4 
5 
5 
5 
7 
6 
5 
4 
1 
1 


1 

2 

3 
2 
3 

7 

5 
7 
4 
5 
2 
3 
1 
1 


9 
9 
3 
8 
2 
6 
3 
1 
4 
1 




19 






20 
21 
22 


1 
1 


1 


23 




6 


24 




8 


25 




11 


26 




3 


27.... 




8 


28... 




3 
3 
3 
1 


2 


1 

2 


3 
1 






7 


29 

30 


1 


2 




4 




3 
2 


























1 


3 


























4... 


1 


























5 


























6 




























7 


1 


























8 




















i 

1 








9... 


























11 


2 

6 
1 
2 
4 
2 
1 
1 
1 
1 
2 
1 
1 
1 
15 
























13 


























14 


























15 




















1 








16 


























17 




























18 




























23 




























24 




























25 




























26 




























June 3 




























6 




























8 




























13'..... 
























































Total. 


46 


49 


49 


50 


49 


50 


48 


50 


50 


49 


49 


50 


49 


50 



1 Duplicate test started Apr. 20. 

In Table XCII are shown results of feeding tests with several mis- 
cellaneous arsenicals, as specified, used in the self -boiled lime-sulphur 
wash and simply in lime water. As before, twigs were cut from 
peach trees in sprayed plats in orchards and placed under glass 
cylinders. Spraying was done April 28 and 30, and 50 beetles were 
added to each jar April 30. The beetles in all of these tests were 
fresh, having been jarred from peach trees a day or so previous. An 
accelerated killing effect seems to have followed the use of the com- 
bined self-boiled and arsenical sprays, as compared with the arsenical 
used alone. The comparatively slow action of arsenate of iron is 
again noted, though when used in the lime-sulphur wash it compares 
favorably with arsenate of lead. 



188 



THE PLUM CURCTJLIO. 



Table XCII.— Tests of killing effect of various arsenicals on the plum curculio on peach, 

Georgia, 1910. 





Beetles dying from each of the arsenicals. 




•6 
cd 
t>> 

03 

FH 
ft 
CO 

o 

a> 
,3 
O 


Arsenicals used in self-boiled lime sulphur. 


Arsenicals used without 
lime sulphur. 


Dates of death, of beetle. 


ea 

CD 

o 

2 

Oj 

a 

CD 
< 


CD 

H 

PI . 

CD^, 

CSr-3 

§! 

o i3 


a 
o 

s « 

03 ft 
Pl w 
CD 

H 

<1 


"2 
3 

W CD 

2 5 
g ft 

H 


o . 

o ft 


u 

CD 

fll 

So. 

J-< ^ 

«£ 

CD ft 


CD 
03 

a 

CD ^ 

V o 

6 " 

ft 

■3 


CD 
03 
PI . 

03,3 

tH 

CD 


a 
o 
.B 

CD 
CD'S 

CD W 

< 


CD CO 
O) 03 

*a 

O ft 


o 

CD 

"S 
a 

m <3 
ol -0 
O M 
ft 

ft 

0Q 


May 2 




3 
5 
6 
7 
11 
9 
3 
2 
4 


4 
4 
3 
4 
5 
9 
3 
1 
2 
3 
2 
6 
2 
2 


3 
3 
1 
3 
10 
10 
2 
7 
1 
3 
3 
1 
1 


11 

8 
7 
5 
2 
8 
5 
1 

1 
1 


2 
2 
5 
12 
9 
8 
1 
3 
1 
3 
1 


n 

7 

15 
8 
1 
3 
1 
1 
1 


3 
3 

8 

7 

20 

6 

1 
1 


1 

2 
5 
2 
8 
1 
4 
2 
5 
4 


7 
1 
1 
1 
4 
9 
4 
2 
4 
1 
5 


3 
16 
3 
2 
1 
8 
9 
5 
1 
2 


1 

6 
3 
3 
5 
4 
4 
10 
4 
3 


3 




4 


1 


5 


6 




7 


1 


8 


9 




10.. 




11 


2 


12 








13 


6 
1 
2 
4 
3 








1 


14 








7 
4 
2 


2 
1 
1 






15 












1 


16 














18 


















1 


19 
























20 


















1 


2 






23 


1 
1 
1 
2 




















24 
























25 
























26 
























27 


















1 

1 






29 
























June 3 


1 

1 
1 

18 






















6 
























8 
























13 
















































Total 


46 


50 


50 


48 


49 


47 


48 


49 


48 


47 


50 


49 







A feeding test was made with beetles in lots of 50, using twigs 
bearing fruit and foliage from sprayed trees in the orchard, except 
in case of lot 6, where foliage had been removed. Trees were sprayed, 
April 4 and 5, with arsenate of lead at the rate of 2 pounds to 50 gal- 
Ions of water, and feeding tests started April 5, except with lots 7 
and 8, which were started April 7. It will be noted that all the 
beetles on the sprayed branches were killed within about a week, 
except lot 6, where fruit only was present and the period was length- 
ened. (See Table XCIII.) 



SPRAYING FOR CURCULIO ON APPLE. 



189 



Table XCIII. — Tests of killing effect on the plum curculio of arsenate of lead sprayed 
on peach foliage and fruit, Georgia, 1910. 





Beetles dying in each lot. 


Date of death of 
beetle. 


Lotl: 

Un- 

sprayed 

twigs 

with 

fruit and 

foliage. 


Lot 2: 

Sprayed 

twigs 

with 

fruit and 

foliage. 


Lot 3: 
Un- 

sprayed 
twigs 
with 

foliage 
only. 


Lot 4: 
Sprayed 
twigs 
with 
foliage 
only. 


Lot 5: 
Un- 
sprayed 
twigs 
with 
fruit 
only. 


Lot 6: 

Sprayed 
twigs 
with 
fruit 
only. 


Lot 7: 

Un- 
sprayed 

twigs 

with 
fruit and 
foliage. 


LotS: 

Sprayed 

twigs 

with 

fruit and 

foliage. 


Apr. 6 . 


1 
1 


3 
3 
6 

8 
15 
4 
7 
1 








2 
1 
3 
3 

14 
1 
1 
7 
2 
2 
1 






7 












8 




4 
22 
19 
4 
1 






2 


9... 








2 


12 


10 


4 






16 


11 


2 
1 
2 






6 


12... 




1 
1 




9 


13 


i 




5 


14 








15 
















16... 






2 
3 










17 .. 































Condition on Apr. 17. 


Lotl. 


Lot 2. 


Lot 3. 


Lot 4. 


Lot 5. 


Lot 6. 


Lot 7. 


LotS. 


Total died 


7 

42 

1 


47 


10 

36 

4 


50 


2 
46 
2 


37 
9 

4 


2 
46 

7 


£0 








3 













Some feeding tests made by Mr. Johnson to determine the possi- 
bility of preventing the fall-feeding punctures of the curculio on 
apple are interesting: 

August 17, a branch of Baldwin apple tree bearing fruit, after 
spraying with arsenate of lead at the rate of 3 pounds to 50 gallons 
of water, was inclosed in a cage with 50 beetles. Twenty beetles had 
died by August 28. An examination of the apples showed 3 without 
punctures and 8 with punctures, as follows: Fruit No. 1, 5 punctures; 
No. 2,7; No. 3, 14; No. 4, 15; No. 5, 16; No. 6,28; No. 7,41; No. 8, 
49; a total of 175 punctures on the 8 fruits. 

The condition of a check branch bearing 8 apples on this date was : 
Fruit No. 1, 66 punctures; No. 2, 14; No. 3, 45; No. 4, 18; No. 5, 26; 
No. 6, 58; No. 7, 23; No. 8, 63; a total of 343 punctures. None of 
the beetles was dead in this cage and the punctures were much larger. 

SPRAYING FOR THE CURCULIO ON APPLE. 



EARLY EXPERIMENTS. 

The first experiments of which we are aware, made to determine 
the value of arsenicals in the control of the curculio on apple, are 
those reported by Forbes in 1885, and already referred to (p. 181). 
In this work 8 trees were used, 4 of them being sprayed and 4 re- 
reserved as checks. Two of the trees were treated with Paris green, 
1 with London purple, and 1 with lime. Two applications were 



190 THE PLUM CURCULIO. 

made 8 times, beginning June 9 and continuing until September 3. 
The two trees sprayed with Paris green at the rate of 1 pound to 50 
gallons of water showed a benefit in lessening curculio injury as com- 
pared with the unsprayed trees of about 50 per cent — more exactly, 
72.70 per cent of the fruit was uninjured as against 42.70 per cent 
uninjured on the unsprayed trees. The trees that had been sprayed 
with London purple gave 61 per cent sou'nd fruit as against 62 per 
cent fruit from the unsprayed trees. In conclusion Prof. Forbes 
states : 

Furthermore, if we must judge from results thus far reached, these various appli- 
cations are all of too slight effect upon the apple for plum curculios to make them 
worth use against these insects, Paris green diminishing curculio blemishes less than 
one-half, London purple about one-fifth, and lime not far from one-fourth. 

No further experiments seem to have been made until 1900, at 
which time Prof. Steclman began, an investigation of the curculio on 
apple, which was continued during 1901 and 1902, the results of 
which are given in the bulletin of the Missouri Agricultural Experi- 
ment Station No. 64, published in 1904. Experiments in spraying 
apples were made in three different orchards. It was desired to test 
the practicability of killing the beetles while they were feeding on 
the leaves before the appearance of the bloom. One-half of each 
orchard was sprayed twice from the time the leaves opened until 
the blossoms opened, leaving the other half as check. These exper- 
iments were repeated the following year, and in addition four appli- 
cations were given after the falling of the blossoms at intervals of 
10 days. By this means about 60 per cent of the fruit was protected 
in spite of reinfestation of the sprayed trees from the unsprayed 
part of the orchard. The desirability of spraying the entire orchard 
to prevent overflow was pointed out, as under these conditions the 
benefits would be very marked, and the great bulk of the "stings" 
would be prevented. 

In the report of the Illinois State Horticultural Society for 1902, 
page 158, Prof. E. S. Titus discusses the plum curculio under the 
caption "Insects other than the codling moth injurious to the fruit of 
apple," and gives results of observations made at the instance of 
Dr. Forbes. In regard to the use of arsenicals he says: 

The experiments tried in the Illinois entomologist's office several years ago showed 
very clearly that the curculio may be killed by spraying trees to which it resorts in 
early spring with Paris green or other arsenical poisons, as it feeds at that time largely 
on young leaves. Consequently, other things being equal, that orchard will be least 
infested and its fruit least injured whose trees are sprayed early in the spring, as for the 
codling moth or canker worm. On the whole, however, much the most promising 
and important measure is the prompt destruction of fallen apples to prevent the escape 
of the curculio larvse into the earth, after which it is almost impossible for these 
larvae to go through their usual transformation. 



SPRAYING FOR CURCULIO ON" APPLE. 191 

The first attempt, however, to determine the possible value of 
the use of arsenical poisons in the control of the curculio on apple on a 
commercial scale was begun by Prof. C. S. Crandall, of the Illinois 
Experiment Station, in 1903. His report of operations for that year 
was read before the Illinois State Horticultural Society (vol. 37, pp. 
176-189). Two blocks of sixty 18-year-old trees each in two different 
but adjacent orchards were selected. In the Williams orchard the 
soil was covered for the most part with a bluegrass sod with a heavy 
surface mulch of dead leaves and grass. In the Blair orchaid there 
was no sod but a scattered growth of plants, including grasses, and 
the surface mulch of leaves and trash was lighter. From 7 to 16 
applications of an arsenical spray were given to the respective plats, 
including Paris green, arsenate of lead, white arsenic, and arsenite of 
lime, the first three treatments in Bordeaux mixture and the sub- 
sequent ones in water. During the course of the work 29,943 apples 
were examined. In commenting on the results, Prof. Crandall 
states that the spraying did not control the curculio. Apparently 
the frequent spraying had some influence because the percentage of 
uninjured fruit from the plats sprayed 16 times was a little higher 
than from any other plats. Three reasons were assigned for the 
unfavorable results, namely : 

1. Weather conditions of early spring and their bearing on the 
crop. 

2. Location of the plats directly in the midst of large orchards con- 
tiguous to native woodlands. 

3. Unusual abundance of the insects. 

On the Williams orchard the percentage of sound fruit varied from 
1.26 to 5.29, with an average for all plats of 2.76. Kesults were 
somewhat better in the Blair orchard, the percentage of sound fruit 
ranging from 2.55 to 16.07, with an average for the several plats 
of 7.13. 

Prof. Crandall continued his work during 1904, as reported for the 
Illinois Horticultural Society (vol. 38, p. 75), and selected a somewhat 
isolated 5-acre orchard, thus eliminating invasion by the insect from 
outside sources. This entire orchard Was treated, except the 13 
check trees. The ground was not in sod and the orchard had never 
been sprayed. The spring weather was reasonably favorable and 
the trees bore a fair crop of fruit, and the curculios were much less 
abundant than in 1903. The schedule of applications was the same 
as employed in 1903. A total of 72,922 apples was examined from all 
of the plats, of which 23 ; 956 were windfalls. The treatments and 
results are shown in Table XCIV. 



192 THE PLUM CURCULIO. 

Table XCIV. — Results of spraying apples for plum and apple curculios in Illinois, 1904. 



Plat 
No. 



Treatment. 







Total 




Total 


number 


Trees. 


number 


of fruits 




of fruits. 


punc- 
tured. 


13 


10,185 


7,617 


14 


14,352 


7,931 


13 


10,861 


4,118 


15 


12,735 


7,066 


13 


11,592 


6,321 


12 


13, 197 


7,310 



Percent- 
age of 
sound 
fruit. 



I... 
II.. 

III. 
IV. 
V.. 
VI. 



3 applications Bordeaux mixture and Paris green (check). 

10 applications Paris green, J pound to 50 gallons water 

16 applications Paris green, £ pound to 50 gallons water.. . 

8 applications Paris green, \ pound to 50 gallons water 

7 applications arsenite of lime 

7 applications arsenate of lead 



25.21 

44.74 
62.08 
44.52 
45.47 
44.61 



All of the plats, including the check (Plat I), were sprayed three 
times with Bordeaux mixture and Paris green, one-fourth pound to 50 
gallons of the Bordeaux, to protect from apple scab and the codling 
moth, and three sprayings on the checks reduced curculio injury, 
as shown by other trees in the orchard entirely unsprayed, 15.21 per 
cent. The marked influence of seasonal and local conditions on 
curculio injury is very forcibly shown in the Illinois results. The 
treatments in 1903 showed no benefit as regards control of the insect, 
whereas in another orchard in 1904 the saving in fruit from trees 
liable to injury ranged from 27.65 per cent to 54.53 per cent. Prof. 
Crandall states: 

To sum up the matter of spraying for the curculio from the standpoint of results 
obtained during the two seasons of 1903 and 1904, it seems possible that under favorable 
conditions and with a reasonable number of applications to control curculios to the 
extent of from 20 to 40 per cent of the possible injury. There is benefit to be derived 
from spraying but not that degree of benefit which would warrant commendation of 
spraying as the one great panacea of injury done by the curculio. 

In the proceedings of the Illinois Horticultural Society for the 
year 1904 (p. 91) Dr. Forbes, in continuation of his study of the 
curculio in Illinois apple orchards begun in 1901, reports results of 
experiments with arsenical sprays carried out in Southern Illinois 
and independent of the researches of Prof. Crandall, just alluded to. 
Four plats were established, including the check, and 4, 6, and 8 
applications of arsenate of lead were given, beginning May 6 to 1 0, when 
the trees were in first full bloom, and repeated at intervals of about 
10 days, ending July 28. Prof. Forbes presents the figures of yield 
of sound and injured fruit, though the experiment loses some of 
its value for the reason that the trees were of different varieties and 
the plats not all under the same conditions, being located in three 
different orchards, although all were on the same farm. Prof. 
Forbes summarizes as follows: 

Finally, to sum up in a word the most important practical results of the orchard 
experiment with arsenate of lead, we may say that four sprayings, apple trees of old 
varieties exposed to a very heavy attack by the plum curculio, the first spraying 
applied in early May just as the trees were coming into bloom and the others at intervals 
of 10 days thereafter, the whole operations costing 17 cents per tree, may be expected 



SPBAYIISTG FOR CURCULIO ON APPLE. 193 

to increase the yield of the orchard about one-half, to increase the average size of the 
fruit about one-fifth, and so to improve the quality of the apples that they should be 
worth from 2\ to 3 times as much as if the orchard had not been sprayed. 

These experiments were also reported in a paper before the Ameri- 
can Association of Economic Entomologists, December, 1904, and in 
Bulletin 108 of the Illinois Agricultural Experiment Station, in 
which latter publication data are given showing the considerable 
movement of the beetles from the check to adjacent sprayed plats, a 
factor in results which has not heretofore been given sufficient con- 
sideration. 

EXPERIMENTS BY THE BUREAU OF ENTOMOLOGY. 

During the past few years the Bureau of Entomology has carried 
out spraying experiments against the curculio in different parts of 
the country and under varying orchard conditions. The importance 
of the subject warrants the presentation of results in some detail. 

EXPERIMENTS AT ANDERSON, MO. 

The work at Anderson, Mo., was under the immediate direction of 
Mr. F. W. Faurot and was accomplished in cooperation with the 
Missouri State Fruit Experiment Station. The orchard consisted of 
a fair selection of varieties of 1 1-year-old trees in good condition. In 
addition to the purely demonstration spraying for insects and dis- 
eases, a test of dusting against spraying was planned on the Lan- 
singburg variety of apple. The block of Lansingburgs consisted of 
6 rows across one end of an 80-acre orchard and was divided into 6 
plats, including the check. In Table XCV Plat II is omitted, as it 
duplicates Plat III, except that a less number of treatments was 
given, namely 9. This variety bore a good one-fourth crop. The 
dust was applied with a power duster driven by a gasoline engine. 
The liquid spray was also applied with a gasoline-power outfit except 
for the application immediately following the falling of the petals. 
The soft condition of the ground at this time from rains necessitated 
the use of a barrel outfit, though the pressure as shown by the gauge 
was maintained at 125 pounds. The plats contained trees as follows: 
I, 32; III, 35; IV, 70; V, 67; VI, 12. The check trees were in two 
rows across the center of the block. The number of trees from 
which all fruit was gathered and counted throughout the season for 
each plat is shown in the table. At the time of the first application, 
March 21 to 24, cluster buds were open; and at the time of the second 
application, April 14 to 16, the petals had been down for 4 or 5 days. 
17262°— Bull. 103—12 13 



194 



THE PLUM CURCULIO. 



Table XCV. — Results of spraying Lansingburg apples for the plum curculio, Anderson, 

Mo., 1908. 




III.. 



IV.. 



V... 



VI. 



Dates of applications. 



pounds, Paris green 2h 
pounds) 



Commercial dust . 



B ordeaux mixture ( 4-4-50) \ 
plus i pound Paris green] 



Bordeaux mixture (4-4-50) 
plus 2 pounds arsenate of 
lead 



Untreated. 



15 29 



3 p. 
a ft 



255 
189 
7S4 
240 
380 



1,5 



926 

1,037 

668 

574 



3,693 



640 
835 
772 
309 
427 
594 



3,577 



1,397 

1,043 
757 
815 

1,0,47 
426 

1,205 



6,690 



169 
30S 

235 
298 
400 
368 
585 
516 
626 



3,505 



"*1 

03 ftj 



248 
17S 
763 
215 
373 



1,777 



757 
785 
500 
369 
464 



2,875 



368 
420 
396 
154 
241 
288 



1,867 



600 
502 
411 
362 
437 
105 
429 



2,846 



166 
297 
219 
286 
389 
364 
544 
481 
566 



2,185 
1,045 
5,657 
1,297 
1,320 



11,504 



3,178 
2,157 
1,135 
1,438 
2,877 



10,785 



789 
762 
698 
337 
419 
529 



3,534 



1,072 
952 
942 
657 
723 
165 
718 



5,229 



1, 

2,104 
1,873 
2,063 
2,448 
2,275 
3,453 
2,741 
2,565 



21,507 



n 9 



2.74 
5.82 
2.67 
1.04 
1. 



18.25 
24 30 
25.15 
35.71 
4.91 



42.50 
49.70 
48.70 
50.16 
43.55 
51.51 



57.05 
51.86 
45.71 
55.58 
58.26 
75. 35 
64.40 



1.77 

3.57 

6.80 

4.02 

2.75 

1. 

7.00 

6.78 

9.58 



MO . 

2®o3 

a> M— i 
> ri ft 

<! 



22.15 



47.81 



57.45 



5.51 



As will be noted, results, so far as preventing puncturing of fruit 
by curculio, were decidedly poor. Plat I, receiving 13 applications 
of a homemade dust, was even more severely injured than the 
block of unsprayed trees, a condition doubtless due to its location. 
Best results were obtained on Plat V, which had the usual demonstra- 
tion treatment, giving 57.45 per cent of sound fruit as against 
5.51 per cent of sound fruit on the unsprayed trees. 

The effect of the treatments on the curculio may be judged, per- 
.haps, by the number of punctures per fruit. Thus, Plat I had an 
average of 6.22 punctures per fruit; III, 2.92; IV, 0.98; V, 0.78; and 
VI, 6.13. 



SPRAYING FOR CURCULIO ON APPLE. 



195 



EXPERIMENTS IN WESTERN NEW YORK AND NORTHWESTERN PENNSYLVANIA. 

Results of demonstration spraying for apple insects and diseases 
in western New York (Westfield) and northwestern Pennsylvania 
(North East) as bearing on the control of the curculio are given in 
Table XCVI. In the Westfield work the average percentage of apples 
uninjured by the curculio from the 5 sprayed Baldwin trees used 
for counts was 91.07, as against 76.21 on the 5 unsprayed count 
trees, the average number of punctures per fruit for the former 
being 0.08 and for the latter 0.237. 

In the case of Duchess trees at North East, Pa., notably better 
results are shown, which may in part be due to the earlier picking 
of the fruit of this variety, as avoiding late feeding punctures by the 
beetles. The 3 count trees of the sprayed block showed 79.04 per 
cent sound fruit, as against 25.44 from the 3 unsprayed count trees, 
a difference, in favor of two applications of poison, of 53.60 per cent 
of the crop. (See PI. XV). 

Table XCVI.— Results of spraying apples for the plum curculio. 

WESTFIELD, N. Y., 1908. 



Plat 
No. 


Treatment. 


Variety. 


Tree 
No. 


Total 
number 
of apples 


Total 
number 
of apples 
punc- 
tured. 


Percent- 
age of 
sound 
apples. 


Average 
percent- 
age of 
sound 
apples. 




[Four applications Bordeaux mix- 
1 ture (4-4-50) plus 2 pounds 
| arsenate of lead: May 6, May 
I 27, June 8, June 27. 


l-Baldwin 

....do 


1 • 

i 3. 

1 I 

f 1 

! 2 
i 3 
i 4 
I 5 


1,658 
2,356 
3,380 
1,204 
2,829 


74 
244 
240 
156 

207 


95.53 
89.64 
92.90 
87.00 
92.60 








I 


















11,427 


921 




91.07 










748 
1,518 

862 
1,100 

838 


191 
309 
181 
212 
312 


74.40 
79.60 
79.00 
80.80 
62.77 








II.. 






















5,066 


1,205 




76.21 









NORTH EAST, PA., 1906. 





[Two applications Bordeaux mix- 
i ture (4-4-50) plus 2 pounds 
[ arsenate of lead: May 24, June 7. 


[Duchess Old- 
[ enberg. 

do 




802 
541 
370 


156 
154 
49 


80.54 
71.55 
86.75 




I 














1,713 


359 




79.04 










647 
268 
146 


473 

223 

95 


26.89 
16.79 
34. 93 




II.... 


















1,061 


791 




25.44 









196 



THE PLUM CUECULIO. 



EXPERIMENTS AT SILOAM SPRINGS, ARK. 

In the one-spray versus demonstration treatments for the codling 
moth and apple diseases at Siloam Springs in 1909 special attention 
was given to determining the effect of these treatments on the cur- 
culio. The results from only Plats I, IV, and V are given as consti- 
tuting the principal features of the work. The orchard was an 
isolated one and contained 344 trees and was divided into five plats. 
There was a miscellaneous assortment of varieties, but principally 
Ben Davis, on which variety all counts were made. The treatments 
which the respective plats received are shown in Table XCVIL 

Plat I shows an increase in uninjured fruit over the unsprayed plat 
(Plat V) of 77.20 per cent, and there is a difference in favor of Plat 
IV of 3.74 per cent of sound fruit. It will be noted that one drench- 
ing spray in this instance gave somewhat better results than five 
applications, though this condition is probably to be accounted for 
by reason of the proximity of Plat IV to the check plat. 



Table XCVII. 



-Results of spraying apples for the plum curculio, Siloam Springs, 
Ark., 1909. 



Plat 
No. 


Treatment. 


Variety. 


Tree 
No. 


Total 
number 
of apples. 


Total 
number 
of apples 
punc- 
tured. 


Total 
number 
of punc- 
tures. 


Percent- 
age of 
sound 
apples. 


Average 
percent- 
age of 
sound 
apples. 




One spraying only with 
arsenical; drenched 
with arsenate of lead, 
1 pound to 50 gallons 
water, Apr. 24-25; Bor- 
deaux mixture only 
(4-4-50) May 25-26, 
July 2. 

Five applications Bor- 
deaux mixture (3-3-50) 
plus 2 pounds arsenate 
of lead: Apr. 24-25, 
May 25-20, July 2, 
July 22, Aug. 10. 


Ben Davis.. 
....do 

do 


( 1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 

f 1 
2 
3 

4 
5 
6 

7 
8 
9 
10 
11 

1 
2 
3 
4 
5 
6 
7 
8 
9 

10 

11 

12 

. 13 


5,689 
4,813 
3, 796 
2,750 
3,446 
3,768 
3,307 
5,443 
3,644 
2,652 
3,895 


1,179 
915 
687 
387 
208 
532 
370 
706 
364 
216 
335 


1,979 

1,713 

2,613 

683 

268 

1,012 

638 

1,200 

642 

319 

642 


79.27 
80.98 
81.90 
85.92 
93.96 
85.88 
88.81 
87.02 
90.01 
91.85 
91.39 




















I 






























43,203 


5,899 


11,709 




86.34 










3,536 
1,890 
5,076 
1,665 
3,145 
1,665 
2,496 
3,172 
4,791 
1,957 
3,058 


746 
301 
437 
74 
266 
200 
498 
467 
1,656 
140 
769 


1,293 
562 
773 
98 
430 
432 

1,025 
877 

3,129 
254 

1,429 


78.90 
84.07 
91.39 
95.55 
91.54 
87.98 
80.04 
85.27 
65.43 
92.84 
74.85 




















IV— 






























32, 451 


5,554 


10,302 




82.88 










2,560 
1,701 
995 
1,538 
1,206 
2,501 
2,821 
1,156 
2,323 
2,258 
1,719 
1,608 
2,060 


2,130 
1,595 

948 
1,522 

999 
2,299 
2,724 
1,070 
1,936 
2,117 
1,605 
1,517 
1,750 


6,623 
6,230 
4,331 

10,068 
3,372 
9,527 

14, 727 
4,714 
6,143 
8,707 
6,921 
• 5,984 
6,739 


16.79 
6.23 
4.72 
1.04 

17.16 
8.07 
3.43 
7.43 

16.65 
6.24 
6.63 
5.65 

15.04 
























V„... 


































24,446 


22,212 


94,086 




9.14 









Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate XV. 




Fig. 1.— Duchess Apples from Trees in Unsprayed Plat. (Original.) 




Fig. 2.— Duchess Apples from Trees in Plat Sprayed Against the Plum Curculio 
with Arsenate of Lead. (Original.) 



BENEFITS OF SPRAYING FOR THE PLUM CURCULIO. 



SPRAYING FOR CURCULIO ON APPLE. 



197 



EXPERIMENTS IN VIRGINIA. 



Experiments in Virginia during 1909 were carried out in two 
localities, namely, at Crozet, in the orchard of Mr. W. S. Ballard, and 
at Mount Jackson, in the orchard of the Strathmore Orchard Co. 

Orchard of Mr. W. S. Ballard. — This orchard is located in the eastern 
foothills of the Blue Ridge and is composed mostly of the Yellow 
Newtown variety, which sort was used exclusively in the experiments. 
The surrounding trees not used in the experiment were sprayed by 
the owner. This work formed part of the "one-spray" experiment, 
and especial attention was given to determining the effect of the 
treatments in lessening curculio injury. Four applications gave a 
percentage of 86.89 sound fruit as against 54.02 on the untreated 
trees, a difference of 32.87 per cent. One single drenching applica- 
tion protected from the curculio to an extent of 73.93 per cent, an 

improvement over the check of 19.91 per cent. (See Table XCVIII.) 

i 
Table XCVIII. — Results of spraying apples for the plum curculio, Crozet, Va.,1909. 



Plat 
No. 


Treatment. 


Variety. 


Tree 
No. 


Total 
num- 
ber of 
apples. 


Total 
num- 
ber of 
apples 
punc- 
tured. 


Total 
num- 
ber of 
punc- 
tures. 


Per- 
centage 
ofsound 
apples. 


Aver- 
age per- 
centage 
ofsound 
apples. 


I 


[ Four applications Bordeaux mix- 
1 ture (2-2-50) plus 2 pounds ar- 
1 senate of lead: Apr. 27, May 24, 
I June 26, and July 26 and 27. 

("One spraying only, drenched with 
1 Bordeaux mixture (2-2-50) plus 
] 2 pounds arsenate of lead, Apr. 
1 27. 


1 Ne wtown 
j Pippin. 

L..do 
do 


1 

2 
3 

4 
5 
6 

7 
8 

1 
2 
3 
4 
5 
6 
7 
8 

1 

2 
3 

4 
5 
6 

7 
8 


802 
1,459 

719 
2,415 
2,032 
1,308 
3,014 
2,328 


115 
187 
103 
345 
463 
114 
267 
252 


157 
275 
163 
524 
668 
162 
395 
328 


85.66 
87.18 
85.67 
85.71 
77.21 
91. 2S 
91.14 
89.17 






14,077 


1,S46 


2,672 




86.89 


II.... 


2,578 
2,533 
5,105 
1,318 
3,245 
1,979 
2,041 
2,039 


961 
730 
1,347 
238 
719 
405 
521 
511 


1,510 

1,290 

2,143 

360 

1,095 

647 

775 

823 


62.72 
71.17 
73.61 
81.94 
77.84 
79.53 
74.47 
74.93 






20,838 


5,432 


8,643 




73.93 


nr. 


3,423 
3,682 
816 
1,016 
3,111 
2,988 
1,980 
2,091 


1,255 
1,571 
437 
531 
1,415 
1,193 
1,098 
1,285 


2,746 
2,571 
705 
962 
2,490 
1,939 
1,865 
2,300 


63.33 
57.33 
46.45 
47.73 
54.52 
60.00 
44.54 
3S. 54 














19,107 


S.785 


15,578 




51. C 2 



198 



THE PLUM CURCULIO. 



Orchard of the Strathmore Orchard Co. — In the Strathmore orchard, 
at Mount Jackson, the curculio was notably more abundant, and the 
results were less favorable. The orchard had been in sod for some 
years and conditions were thus favorable for the insect. All trees 
not included in the experiment were sprayed by the owners. 

The results indicate the impracticability of satisfactorily reducing 
curculio injury by spraying alone, when conditions are extremely 
favorable for the insect. Three applications protected the fruit to 
an extent of 40.82 per cent as against 27.23 per cent on the unsprayed 
trees, a gain of 13.59 per cent of the crop. Curiously, the single 
application, given to Plat II, resulted in a higher percentage of sound 
fruit than the three treatments given to Plat I, namely, 57.90, an 
increase over the check plat of 30.67 per cent. 

TableXCIX. — Results of spraying apples for the plum curculio, Mount Jackson, Va.,1909. 



Plat 
No. 


Treatment. 


Variety. 


Tree 
No. 


Total 
num- 
ber of 
apples. 


Total 
num- 
ber of 
apples 
punc- 
tured. 


Total 
nuJi- 
ber of 
punc- 
tures. 


Per- 
centage 
ofsound 
apples. 


Aver- 
age per- 
centage 
ofsound 
apples. 


I 


(■Three applications Bordeaux mix- 
1 ture (1-1-50) plus 2 pounds ar- 
| senate of lead, May 6-7, 28-29, 
[ July 8-9. 

One spraying only, with arsenical. 
Drenched with arsenate of lead, 
2 pounds to 50 gallons of water, 
May 6-7. Bordeaux mixture 
only (2-2-50), applied May 28-29 
and July 8-9. 


[•Ben Davis.. 
....do 
do 


f 1 
2 
3 

4 
5 
6 

7 
8 

1 
2 
3 
4 
5 
6 
7 
8 

' 1 
2 
3 
4 
5 
6 
7 
8 


1,866 
1,308 
3,466 
708 
1,667 
3,786 
1,063 
2,429 


1,367 
755 

1,631 
441 

1,257 

2,197 
612 

1,382 


2,961 
2,391 
3,067 
932 
3,013 
4,040 
1,486 
2,869 


26.74 
42.28 
52.94 
37.71 
24.59 
41.97 
42.42 
43.10 






16,293 


9,642 


20,759 




40.82 


II.... 


3,827 

3,657 

675 

989 

1,679 

3,480 

969 

4,299 


1,507 

1,788 
303 
494 
754 

1,212 
447 

1,735 


2,782 
1,800 

633 
1,032 
1,449 
2,159 

987 
3,153 


60.62 
51.10 
55.11 
50.05 
55.09 
65.17 
53.86 
59.64 






19,575 


8,240 


13,995 




57.90 


III... 


3,926 
3,109 
1,840 
1,508 
3,189 
4,153 
5,121 
2,795 


3,186 
2,226 
1,079 
1,226 
2,399 
2,823 
3,611 
2,107 


7,336 

4,497 
2,212 
2.S88 
5,030 
, 6,122 
8,779 
4,904 


18.84 
28.40 
41.36 
18.09 
24.77 
32.04 
29.48 
24.61 














25,641 


18,657 


41,768 




27.23 



EXPERIMENTS AT ST. JOSEPH, MO. 

The work at St. Joseph also formed part of a demonstration sched- 
ule of spraying in comparison* with the one-spray method. The 
orchard used had been in sod for some years, and no spraying had 
been done. Conditions were especially favorable for the insects, 
and, as shown by the tabulated results below, the injury under these 
conditions was very severe. The crop, moreover, was light by reason 



SPEAYING FOR CURCULIO ON APPLE. 



199 



of late spring frosts, which served to concentrate the injury. Unques- 
tionably a part of the loss shown was due to the apple curculio, which 
was abundant in that locality. At the time of the first application, 
May 16, the petals had just fallen from the trees. The St. Joseph 
results present some points similar to those obtained the same year at 
Mount Jackson, Va., — namely, that when the curculio is excessively 
abundant, satisfactory results may not be obtained by spraying. 
Plat I, which received 4 applications, shows only 50.10 per cent of 
sound fruit as against 4.05 from the unsprayed trees, representing a 
gain of 46.05 per cent. The single drenching application, given to 
Plat II, resulted in 36.80 per cent of fruit free from curculio, a gain 
over the unsprayed block of 32.75 per cent of the crop. 

Table C. — Results of spraying apples for the plum curculio, St. Joseph, Mo., 1909. 



Plat 
No. 


Treatment. 


Variety. 


Tree 
No. 


Total 
num- 
ber of 
apples. 


Total 
num- 
ber of 
apples 
punc- 
tured. 


Total 
num- 
ber of 
punc- 
tures. 


Per- 
centage 
of sound 
apples. 


Aver- 
age per- 
centage 
of sound 
apples. 


I 


(Four applications Bordeaux mix- 
1 ture (4-4-50) plus 2 pounds ar- 
| senate of lead: May 16, June 9, 
[ July 9, and Aug. 6. 

(One application. Drenched with 
< arsenate of lead, 2 pounds to 50 
I gallons water, May 16. 


>Ben Davis . . 

L..do 

do 


{} 

{ i 

ii 


1,747 
1,624 
1,579 


966 
660 
844 


2,443 
1,355 
2,012 


44.70 
59.35 
46.54 






4,950 


2,470 


5,810 




50.10 


II.... 


2,769 
3,019 


1,909 
1,749 


5,054 
4,236 


31.05 
42.06 






5,788 


3,658 


9,290 




36.80 


Ill 


1,694 
1,437 
1,358 


1,625 
1,398 
1,284 


7,715 
8,577 
5,275 


4.07 
2.71 
5.44 














4,4S9 


4,307 


21,567 




4.05 



The records above given in spraying apple orchards for the cur- 
culio are assembled in Table CI, which indicates, in average per- 
centages, the amount of uninjured fruit from each plat from the 
several localities, arranged according to the number of applications 
given. These experiments have extended over a period of several 
years and were made in various places, so that the results are not 
entirely comparable. Even when considering the results of indi- 
vidual experiments, a wide variation is seen in results from orchards 
which received practically the same treatment — for example, in the 
two orchards in Virginia sprayed during 1909. 



200 



THE PLUM CURCULIO. 



Table CI. — Summary of results in spraying apples for the plum curculio, in average 
percentages of sound fruit, various localities. 





Localities. 


Treatments. 


Illinois. 


Ander- 
son, Mo. 


West- 
field, 
N. Y. 


North 
East, Pa. 


Siloam 

Springs, 

Ark. 


Crozet, 
Va. 


Mount 

Jackson, 

Va. 


St. 

Joseph, 

Mo. 


1 application 










86.34 


73.93 


57.90 


36.80 


2 applications 








79.04 




3 applications 












40.82 




4 applications 






91.07 






86.89 


50 10 


5 applications 








82.88 






7 applications (Paris 
preen) 


45.47 

44.61 

47.80 
44.52 
44.74 














7 applications (arse- 
nate of lead) 


57.45 














7 applications (arse- 
nite of lime) 














8 applications 
















10 applications 
















13 applications (home- 
made dust) 


3.84 
22.15 














13 applications (com- 
mercial dust) 
















16 applications 


62.08 
25.21 














Unsprayed (check)... 


5.51 


76.21 


25.44 


9.14 


54.02 


27.23 


4.05 



CONCLUSIONS. 

The records above given of results of spraying apples for the con- 
trol of the curculio indicate clearly that the injuries of the pest may 
be in all cases greatly reduced, although the degree of benefit varies 
widely. It is apparent that account must be taken of other factors, 
as the relative abundance of the insects as compared with the amount 
of fruit present on the trees. With a small fruit crop and abundance 
of curculios, the most thorough spraying will not serve to bring 
through a satisfactory amount of sound fruit, as will be noted in the 
results of experiments at St. Joseph, Mo. With a large crop of fruit 
and an abundance of insects, results will likewise be disappointing. 
If the curculios for any cause are scarce and there is a large fruit 
crop, injury is of course much less important. In other words, the 
degree of success in spraying varies with the abundance of the insects, 
and where the latter are numerous thorough treatments seem to fail 
to yield a desired freedom from injury. While spraying is undoubt- 
edly a most important adjunct, and if persisted in from year to year 
may answer for its control, as its effects are cumulative, yet it is 
clear that other control measures should also be employed. In all 
cases which have come under our observations the insects have 
always been found most abundant in orchards which are in sod or 
are poorly cared for and allowed to grow up more or less in weeds 
and trash. Also orchards adjacent to woods always suffer severely, 
especially along the border. (PI. XVI.) As opposed to this condition 
is the notably less injury in orchards kept free from weeds and trash. 
In such cases sprayings usually given for other orchard insects, as 
the codling moth, serve to keep this pest well under control. In 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate XVI 




Fig. 1.— Native Plum Thicket in the South, Adjacent to Peach Orchard. 

(Original.) 




Fig. 2.— Woods and Thicket Adjacent to Plum Orchard, Furnishing the Beetles 
with Excellent Hibernation Quarters. (Original.) 

CONDITIONS FAVORING THE PLUM CURCULIO. 



SPRAYING FOR CURCULIO ON APPLE. 201 

fact it may be said as a general statement that the curculio will 
never become seriously troublesome in apple orchards given the 
usual routine attention in cultivation, spraying, pruning, etc., now 
considered essential in successful fruit growing. Serious losses from 
the curculio are almost conclusive evidence of neglect, which is best 
and most quickly corrected by the adoption of proper orchard prac- 
tice. The following schedule of spraying is recommended for apple 
orchards and should control the plum curculio as well as the numer- 
ous other insects mentioned. Where the curculio is excessively 
troublesome a treatment about midway between the third and fourth 
would probably be advantageous. 

SCHEME FOR SPRAYING APPLE ORCHARDS. 1 

First treatment. — Spray with arsenate of lead in Bordeaux mix- 
ture or dilute lime-sulphur solution for apple scab when cluster buds 
are out, but before the blossoms open. This treatment is valuable 
against the bud moth, cankerworms, plum and apple curculios, tent 
caterpillar, etc. 

Second treatment. — As soon as the petals have fallen, spray very 
thoroughly with arsenate of lead in Bordeaux mixture or dilute lime- 
sulphur solution so as to place a dose of poison in the calyx cup of 
each young apple. Larvae of the codling moth, the principal cause 
of wormy apples, hatching some three or four weeks later, mostly 
enter the fruit at the blossom end, and are thus killed. This is the 
most important of all treatments for the codling moth and is valua- 
ble in destroying the lesser apple worm (Enarmonia prunivora), plum 
and apple curculios, cankerworms, tent caterpillars, etc. 

Third treatment. — Three or four weeks after blossoms have fallen 
use arsenate of lead in Bordeaux mixture or dilute lime-sulphur 
solution, thoroughly coating the foliage and young fruit. Tins is 
valuable against the codling moth and affords further protection 
against the insects above mentioned. 

Fourth treatment. — An additional application of the arsenical in a 
fungicide may be necessary, nine or ten weeks after the blossoms 
fall, for the second brood of the codling moth, and, in the Middle and 
Southern States especially, a fifth treatment is advisable two or three 
weeks later. In orchards not infested with the bud moth and canker- 
worms the first treatment may be omitted. The second, third, and 
fourth applications will suffice to give protection from most insect 
pests of the fruit and foliage, supplemented by the fifth for the ter- 
ritory indicated. 

1 Excellent results in control of the curculio and the codling moth have been obtained from a single 
application of an arsenical after the falling of- the petals. The one-spray treatment is most likely to be 
of value for varieties not subject to scab and bitter rot. The reader should obtain copies of reports on 
one-spray method, being Part VII of Bulletin 80 and Part II of Bulletin 115 of this bureau. 



202 THE PLUM CURCULIO. 

SPRAYING PEACHES WITH ARSENIC ALS. 

Until within recent years comparatively little experimentation 
has been done with arsenicals for the control of the curculio on the 
peach. During the past five or six years, however, the subject has 
received attention at the hands of different investigators, and suffi- 
cient data have been accumulated to indicate about how much pro- 
tection may be expected. 

Paris green and London purple were undoubtedly early used on 
the peach, beginning with the first employment of these arsenicals 
against this insect. It was soon noted, however, that the foliage of 
peach was more sensitive than that of other deciduous fruits, and 
for this reason spraying of peaches seems not to have been practiced 
to any great extent. This foliage injury from arsenicals had been 
frequently commented upon and was pointed out by Dr. Forbes in 
1888 and 1889, and also by Prof. Weed, who gave experience of a 
Marion County, Ohio, fruit grower, as follows: 

We accidentally stumbled over the fact that from 60 to 70 gallons of water to one- 
half pound of poison in solution was strong enough to fully check the curculio and 
all or more than the peach tree would stand. We destroyed a plum tree and several 
peach trees with our experiments, and know that 100 gallons to 1 pound of poison in 
solution is too strong for the foliage of some varieties of apples and that it will kill a 
peach or plum tree. My own opinion is that one-half pound of poison to 60 gallons 
is safe, and if applied at the time of the usual bloom of apple and the second time 
10 days later will destroy the leaf-eating insects and the codling moths, but for plum 
and peach one-fourth pound to 40 gallons of water is strong enough and will, if applied 
twice, effectually check the ravages of the curculio without destroying the foliage. 

Despite frequent serious defoliation of trees some peach growers 
undoubtedly continued the use of Paris green and London purple, 
especially in the Northern States. In the South comparatively 
little spraying was done, so far as available records indicate. The 
control of the curculio on peach was therefore largely limited to the 
practice of jarring, and this work was not very generally followed, 
the insect being allowed to continue its depredations unchecked. 
With the increase of commercial peach culture in certain of the 
Southern States, notably in Georgia, and in view of the favorable 
conditions for the multiplication of the pest, its injuries became 
especially serious, not only on account of the fruit destroyed by it, 
but by reason of the prevalence in that section of a serious fungous 
disease of the fruit at about ripening time, namely, the so-called 
brown-rot, which the work of this insect, by its punctures, greatly 
favored. 

Considerable attention has been given during recent years to 
determining, if possible, ways in which Paris green and also copper 
fungicides may be safely used on the peach, notably by Messrs. 



SPRAYING PEACHES WITH ARSENICALS. 203 

Gillette, Galloway, Woods, Fairchild, Sturgis, Baine, and Hedrick. 
It was found that the addition of lime to the Paris green or London 
purple spray greatly reduced its causticity, and the use of Paris 
green in this way was recommended for peach by Haywood, who says : 

In spraying peach trees, none of the Paris greens bought upon the market should 
be used without the addition of lime. 

For peach trees sprayed with the use of lime, the amount of soluble arsenic oxid 
allowable lies between 3 and 6 per cent, a fair average being 4J per cent. 1 

Nevertheless, even with the use of lime two or three applications 
of a Paris-green spray very generally resulted in defoliation of the 
trees, and in recommendations for the use of arsenicals on peaches 
this risk was very generally pointed out and understood by the 
majority of peach growers. 

The development of arsenate of lead, a stable compound con- 
taining practically no free arsenic, it was thought would furnish an 
arsenical which might be used without injury on peaches. Experi- 
ments to determine its usefulness were at once begun by entomolo- 
gists, and while it was noticeably less injurious than Paris green or 
London purple, yet in the South especially several applications, as 
deemed necessary for the control of the insect, caused a considerable 
amount of foliage to fall and often resulted in burning of the fruit. 
Arsenate of lead, however, was generally recommended for peach 
spraying by the manufacturers and also with caution by many 
entomologists and horticulturists. Not a few orchardists who tried 
the poison experienced disastrous results, whereas comparatively 
little injury was noted by others, who preferred to take the risk of 
foliage and fruit injury in preference to suffering the ravages of the 
curculio. 

In a word, opinion was divided as to the advisability of spraying- 
peaches with arsenate of lead, with perhaps on the whole a distinct 
prejudice against it. 

In the course of the present curculio studies particular attention 
has been directed to the question of arsenical injury to peaches. 
During 1906 green arsenoid, Paris green, and arsenate of lead (both 
commercial and homemade) were tried on peaches according to a 
uniform plan of treatment in the Southern, Middle, and Northern 
States, in order to secure if possible comparative data from these 
regions. In all localities the green arsenoid and Paris green (3 
applications each of 4 ounces to 50 gallons of lime water) proved 
injurious, defoliating trees almost completely. In northwestern 
Pennsylvania neither the commercial nor the homemade lead arsenate 
(3 applications at the rate each of 2 pounds to 50 gallons of lime 
water) caused noticeable injury. In Virginia the homemade lead 

i Bui. 82, Bur. Chem., U. S. Dept. Agr., p. 32, 1904. 



204 THE PLUM CTJRCTJLIO. 

arsenate largely defoliated the trees and burned the fruit. There 
was, however, little foliage injury from the commercial arsenate of 
lead, though the fruit was injured and nearly all fell from the trees 
before ripening. In Georgia both forms of arsenate of lead defoliated 
the trees almost completely and injured the fruit to a serious extent, 
the homemade lead arsenate being the more injurious. 

Also, during 1906, in Virginia, several other commercial brands of 
arsenate of lead were tried and no difference between them could be 
distinguished as to their effect on foliage and fruit. Arsenic sulphid 
in paste form, at the rate of 2 pounds to 50 gallons of lime water, was 
applied once and quickly defoliated the trees, killing the twigs and 
smaller branches, resulting finally in the death of several of the trees 
sprayed. During 1907 eight additional brands of arsenate of lead 
were tried in Virginia with from 1 to 4 applications in strength, 
varying from 1 to 3 pounds per 50 gallons of water. These were 
used with and without lime. Two applications at the rate of 2 
pounds to 50 gallons of water, plus 2 or 3 pounds of stone lime, were 
found reasonably safe; and this treatment was adopted for recom- 
mendation to growers, although the risk of possible injury was 
pointed out. 

In cooperation with the Bureau of Chemistry an inquiry was 
started in 1907 to determine if possible the reasons for injury to 
peach foliage from arsenate-of-lead sprays. The results of the work 
during 1907 and 1908 have been stated by Messrs. J. K. Haywood 
and C. C. McDonnell, 1 and conclusions were presented from the ex- 
periments in 1909. These studies have been extensive and are 
interesting as bearing on the causes of the decomposition of lead 
arsenate when sprayed on peach trees, resulting in injury to foliage 
and fruit. The idea of decomposition of the poison by the action 
of the carbon dioxid of the air was disproved by numerous tests, 
but it was found, in an examination of water used in spraying, that 
this contained a sufficient quantity of sodium chlorid (common salt) 
to decompose an appreciable quantity of the lead arsenate; and it 
was concluded that if certain salts commonly present in water were 
present in more than very small quantities they would exert a solvent 
action on the arsenate of lead. Concerning this matter Messrs. 
Haywood and McDonnell state.: 

(1) When applied with spring water (analysis of which has been given), some injury 
to foliage resulted, but it was not nearly so marked as in the preceding year, and a 
longer time elapsed before the injury was noticeable. 

(2) When applied with distilled water very slight injury occurred, noticeably less 
than when the spring water was used. 

(3) When applied with distilled water to which 10 grains per gallon of sodium 
chlorid had been added, rather serious injury resulted. When distilled water con- 

i Bui. 131, Bur. Chem., U. S. Dept. Agr., p. 49, 1910. 



SPBAYING PEACHES WITH AESEISTICALS. 205 

taining 40 grains of sodium chlorid per gallon was used, the injury was very much 
increased, practically 50 per cent of the foliage being affected. 

(4) When applied with distilled water containing 10 grains of sodium carbonate per 
gallon, injury was noticeable 14 days after the first application, and 7 days after the 
third application the trees were almost completely defoliated. 

(5) Applied with distilled water containing 10 and 40 grains of sodium sulphate per 
gallon, some injury resulted, but this was not so marked as that produced in the 
presence of sodium chlorid. 

In similar experiments where lime was added at the rate of 4 pounds to 50 gallons, 
injury to the foliage was almost entirely prevented. 

In view of the above observations as to the possible importance of 
the water used in spraying, the Bureau of Entomology carried out 
spraying experiments in orchards in Georgia during 1910, employing 
9 well-known brands of arsenate of lead, using these in ordinary well 
water and also in rain water, which it was thought would be entirely 
free f?om sodium chlorid and other salts. Three applications of the 
sprays were made, the milk of lime made from 2 pounds of good 
stone lime being added to the spray in each case. With all of the 
brands of arsenate of lead, the first two applications did no appre- 
ciable injury. Th^ third application, given a month before ripening 
of the fruit, however, resulted in serious injury, which began to show 
after a rainy spell about a week after the applications. There 
appeared on the fruit brown sunken spots, which rapidly increased in 
size, causing the fruit to crack and drop to the ground until by picking 
time only 25 per cent still remained on the trees. This was barely fit 
for market purposes, having a dark red, almost black, appearance on 
the side exposed to the sun. These trees were 50 to 90 per cent 
defoliated. No difference in injury was to be detected from the use 
of rain water against ordinary well water. 

These same brands of lead arsenate were used on trees alongside 
in the self-boiled lime-sulphur wash of the formula: Sulphur, 8 
pounds; stone lime, 8 pounds; water to make 50 gallons. In these 
tests none of the fruit was burned enough to cause it to drop, all of it 
being merchantable. Some specimens, however, were so highly 
colored that they were placed in the second grade. About 20 per 
cent of the foliage on these lime-sulphur plats showed some injury, 
but none of it dropped. As regards the comparative injury from the 
different brands of arsenate of lead, very little difference could be 
detected, save in the case of one brand, which showed up about the 
same amount of injury as in the case of the other brands when applied 
in lime-sulphur wash. It was tested, however, on trees in another 
part of the orchard, as it was received too late to be included in the 
block where the balance of the lead arsenates were tried. 

In addition to tests of lead arsenates, certain other arsenicals were 
tried to determine their effect on the foliage and fruit. The toxicity 
of these arsenicals was at the same time being determined in the 



206 THE PLUM CUKCTJLIO. 

laboratory by feeding tests with the beetles. (See p. 186.) In each 
case the miik of lime from 2 pounds of stone lime was used to each 
50 gallons of spray. 

Arsenic sulphid (As 2 S 2 ), f pound to 50 gallons of water, was 
applied once April 29. By June 5 the plat treated with the poison 
in rain water showed injury to almost all of the leaves, with con- 
siderable foliage fallen, and this same condition prevailed on the plat 
treated with the poison in well water. On the lime-sulphur plat less 
than one-half as many leaves were injured and very few leaves had 
fallen. 

Arsenic tersulphid (As 2 S 3 ) , 6 ounces to 50 gallons of water, applied 
April 13 and 24, showed by May 10 about 75 per cent of defoliation of 
all the trees on the 3 plats. 

Red sulphid of arsenic (As 2 S 2 ), 6 ounces to 50 gallons of water, 
applied April 13 and 29, showed on all plats by June 5 a condition 
similar to the arsenic tersulphid plat, though new foliage was coming 
out. 

Sulpho-arsenate of soda, 6 ounces to 50 gallons of spray, showed 
by June 5 about 60 per cent of the foliage fallen, with those remaining 
badly burned and shot-holed. This condition was true on the 3 plats 
where the poison was used in well water, rain water, and the self- 
boiled lime-sulphur wash. 

Arsenate of iron in paste form, 2 pounds to 50 gallons of water, 
applied April 29 and June 16, resulted in no foliage and fruit injury 
whatever throughout the season. 

Arsenate of iron in powdered form, 1 pound to 50 gallons of water, 
applied to the trees April 13 and 29 and June 16, also resulted in no 
injury on any of the plats throughout the season. 

Tests of the killing effect of arsenate of iron on the beetles in the 
laboratory indicated, however, that it is a very slow-killing agent; 
but it is probable that the beetles after first eating of the poison are 
rendered incapable of further important injury. Additional tests 
are planned with this poison on a commercial scale in orchards. 

During 190S and 1909 feeding tests with beetles and also with 
various caterpillars were made, using various compounds regarded 
as more or less toxic, with a view to their possible substitution for 
arsenicals for use on the peach. Among those tried were the 
following : 

Black sulphid of antimony (Sb,^. 
Barium sulphid (BaS). 
Barium carbonate (BaC0 3 ). 
Copper 6ulpho-cyanid (Cu 4 SCN„). 
Carbonate of lead (PbC0 3 ). 
Lead oxid (PbO). 
Zinc oxid (ZnO). 
Zinc cyanid (ZnCN). 



SPRAYING PEACHES WITH ARSENICALS. 207 

None of these, however, gave sufficient promise to warrant field 
tests. 

From the foregoing it will be noted that severe injury has resulted 
from the use on peach of green arsenoid, Paris green, zinc sulphid, 
red sulphid of arsenic, tersulphid of arsenic, and sulpho-arsenate of 
soda. Injury from arsenate of lead has been variable, according to 
season, and especially depending upon the number of applications 
made. Two early treatments of the poison at the rate of not over 
2 pounds to 50 gallons of water, with an equal or greater quantity of 
lime added, have on the whole caused comparatively little injury, 
although in some years injury has been fairly well marked. Three 
applications of lead arsenate in limewater, however, have rather 
uniformly been injurious. No important difference in the burning 
effect of the different brands of arsenate of lead has been detected; 
and according to the tests made in 1910 in the comparison of rain 
water and well water no difference between them was discernible. 

The time between the applications of the poison and the appear- 
ance of injury to the foliage varies, depending upon the arsenical 
in question. Thus Paris green, green arsenoid, and sulphid of 
arsenic promptly show a shot-holing and yellowing of the leaves, 
which later drop more or less completely. (See PI. XVII, figs. 1-6.) 
The injury resulting from lead arsenate is about the same, only it is 
slower to appear. In the case of two applications dropping of the 
leaves may be so gradual as not to attract attention and may be 
largely compensated for by the production of new foliage. A third 
application, however, is generally followed by a decided and prompt 
dropping of the foliage, usually within 10 days or 2 weeks, leaving 
the branches more or less bare and the fruit exposed to the sun. 
Arsenate of lead also produces a notable reddening of the fruit, 
though this reddening is due in part to an increased amount of sun- 
shine following the thinning of the leaves. This increased coloring 
is the subject of common remark by growers, and if but one or two 
applications of the poison have been made is not so pronounced as to 
detract from the appearance of the fruit. A third application, how- 
ever, very generally results in an intense dark-red coloring and the 
associated changes brought about very often result in brown depressed 
areas of variable extent and a cracking on the sunny side of the 
peach. Fruit so injured is worthless and mostly drops before ripen- 
ing time. (See PI. XVIII, fig. 1.) 

For the proper control of the curculio on peach three or four applica- 
tions of the poison would be desirable. However, in view of the injury 
resulting from more than two treatments, recommendations have been 
limited to two timely applications of the poison, and always with the 
addition of limewater. This treatment gave a considerable degree of 
protection and- has recently come into a rather extended use by 
peach growers. 



208 



THE PLUM CURCULIO. 



SOME RESULTS OF SPRAYING PEACHES FOR THE CUROULIO. 

In the following tables some results of spraying peaches for the 
curculio are presented. The benefits are seen to vary from season 
to season, as in the case of the apple, depending upon the abundance 
of the insects. On account of the difficulty of taking note of punc- 
tures in the fuzzy peaches, the results are based on records of actual 
infestation of fruit by larvae or indications of the presence of the 
latter. The results obtained by this method of computation on the 
different plats should be entirely comparable. Examinations were 
made of all drop fruit during the season, as well as of the ripe fruit 
at picking time. One of the most important results in spraying for 
the curculio is the reduction of brown rot. The punctures of the 
curculio in the fruit form an easy point of infection, and very notable 
benefits in the reduction of brown rot may be observed in orchards 
sprayed only for the curculio. 

In Table CII are given results of spraying of peaches in 1906 on 
the Arlington Farm, Va. The orchard used contained about 500 trees 
and was an isolated one, but adjacent to a thick growth of young 
trees and bushes. Not all of the trees were treated, each plat con- 
taining some 50 trees. The applications were made on the dates 
indicated in the table. It was also thought desirable to determine 
the possible benefit of spraying the trees heavily with simply lime- 
water, inasmuch as this method of curculio control has been some- 
what exploited. 

Table CII. — Results of spraying peaches for the plum curculio, Arlington Farm, Va., 

1906. 





Treatment. 


Tree 

No. 


Fruit from 
ground. 


Fruit from 
tree. 


Total 
num- 
ber of 
fruit. 


Total 
num- 
ber of 
fruit 
infest- 
ed. 


Per- 
centage 

of 
sound 
fruit. 


Aver- 
age 


Plat 
No. 


To- 
tal. 


In- 
fest- 
ed. 


To- 
tal. 


In- 
fest- 
ed. 


percent- 
age of 
sound 
fruit. 


I 


Three applications, 2 pounds arse- 
nate of lead to 50 gallons water, 
T>lus 3 pounds stone lime: Apr. 
27; May 8 and 20. 

Three applications, whitewash lime 
15 pounds to 50 gallons water: 
Apr. 27; May 8 and 20. 


f 1 
2 

1 3 

i 4 
[ 5 

f 1 
i 2 
\ 3 
! 4 
( 5 

f 1 

I 2 
1 3 
I 4 
I 5 


773 
1, 007 
646 
743 
423 


7 
35 
23 

4 
74 


444 
674 
220 
350 
179 


14 
7 
8 
7 
9 


1,217 

1,741 
866 

1,093 
602 


21 
42 
31 
11 
83 


98.27 

97.58 
96. 42 
98. 99 
86.21 






3,652 


143 


1, 867 


45 


5,519 


188 




96.59 


II.... 


393 
309 
419 
554 

548 


37 

56 

118 

79 

78 


83 
254 
136 
345 
250 


12 

18 

30 

9 


476 
563 
555 
899 

798 


37 

68 
136 
109 

87 


92.22 
87.90 
75. 49 
87.87 
89.09 






2,223 


368 


1,008 


69 


3.291 


437 




86.72 




374 
243 
201 
440 
830 


108 

64 

47 

140 

234 






374 
579 
201 
558 
900 


10S 

80 

47 

151 

236 


71.12 
85.14 
76. 61 
72.93 
73.77 




III. 


336 


22 








118 
70 


11 
2 






2,088 


593 


524 


35 


2,612 


628 




75.96 



The curculio was not especially abundant in this orchard during 
1906; as shown by the condition of the check, about 25 per cent of 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate XVII. 




Bui. 103, Bureau of Entomology. U. S. Dept. of Agriculture. 



Plate XVIII. 




Fig. 1 .— Elberta Peach Sprayed Three Times with 
Arsenate of Lead, Showing Burning and Cracking 
Effects of the Poison. (Original.) 




Fig. 2.— Japanese Plums, Showing Burning from one Application of Arsenate 
of Lead. (Original.) 



ARSENICAL INJURY TO FRUIT 



SPRAYING PEACHES WITH ARSE NIC ALS. 



209 



the fruit was infested. Nevertheless, the results show a certain 
benefit, there being a gain in uninjured fruit on the plat treated with 
arsenate of lead of 20.63 per cent, and on Plat II, treated with lime 
of 10.76 per cent. 

Results obtained also in 1906 at Myrtle, Ga., are shown in Table 
CIII. The trees treated were located in an 8-acre block of the 
Georgia Belle variety, composing a 200-acre orchard. The treated 
area, however, was on one side of the orchard and fairly well separated 
from the main body of the trees. Conditions for the curculio were 
here ideal on account of adjacent woods, and the presence here and 
there through the orchard of terraces which had become overgrown 
with bushes, weeds, etc. Each plat comprised 50 trees. The dates 
and character of applications are shown in the table, as well as the 
number of trees -on which records were taken. 

The average percentage of sound fruit on the untreated trees was 
67.59 per cent. As compared with this injury there is a gain in 
sound fruit on Plat I, spraj _d with arsenate of lead, of 21.04 per cent, 
and on Plat II, sprayed with lime, of 2.20 per cent. 

Results of spraying peaches at Mayfield, Ga., for the curculio in 
1908 are shown in Table CIV. This work was carried out by the office 
of the Georgia State entomologist according to a plan furnished by 
this bureau. Each plat contained 60 trees of the Elberta variety, 
and while a sufficient number of trees was not used for making counts 
of the fruit, the results are nevertheless significant. 

Table CIII. — Results of spraying Georgia Belle peaches for the plum curculio, Myrtle, 

Ga., 1906. 









Fruit from 


Fruit from 




Total 




Aver- 








ground. 


tree. 


Total 


num- 


Per- 


age 


Plat 


Treatment. 


Tree 
No. 










num- 
ber of 
fruits. 


ber of 

fruits 

in- 
fested. 


age of 
sound 
fruit. 


cent- 
age of 
sound 
fruit. 


No. 


Total. 


In- 
fested. 


Total. 


In- 
fested. 






f 1 


18 


4 


121 


- 27 


139 


31 


77.69 








2 


28 


6 


171 


4 


199 


10 


94.97 








3 


47 


7 


144 


4 


191 


11 


94.24 








4 


39 


13 


135 


9 


174 


22 


87.35 




I 


Three applications homemade ar- 


5 


33 


10 


180 


5 


213 


15 


92.95 






senate of lead 2 pounds to 50 


G 


10 


4 


81 


5 


91 


9 


90.10 






gallons of water plus 3 pounds 


7 


38 


22 


213 


8 


251 


30 


88.04 






stone lime: Apr. 10, 21, and 30. 


S 


14 


3 


80 


5 


94 


8 


91.48 








9 


42 


16 


266 


16 


308 


32 


89.61 








10 


23 


11 


92 


15 


115 


26 


77.38 








11 


14 


4 


48 


7 


62 


11 


82.25 








I 12 

r l 


27 


14 


134 


8 


161 


22 


86.33 






333 


114 


1,665 


113 


1,998 


227 




8S.63 




2 


1 


24 


2 


26 


3 


88. 46 








2 


10 


4 


32 


12 


42 


16 


61.90 








3 


66 


10 


77 


9 


143 


19 


86.71 








4 


10 


6 


29 


3 


39 


9 


76.92 




IL... 


Three applications of whitewash, 


5 


33 


20 


69 


16 


102 


36 


65.70 






15 pounds lime to 50 gallons 


6 


17 


4 


59 


13 


76 


17 


77.63 






water (no arsenical): Apr. 3, 13, 


7 


28 


16 


63 


23 


91 


39 


57.14 






and 21. 


8 


27 


15 


144 


35 


171 


50 


70.76 








9 


22 


12 


46 


9 


68 


21 


69.11 








10 


7 


1 


16 


6 


23 


7 


69.56 








11 


27 


13 


31 


IS 


58 


31 


46.55 








I 12 


50 


37 


220 


50 


270 


87 


67.74 






299 


139 


810 


196 


1,109 


335 




69.79 



17262°— Bull. 103—12 14 



210 



THE PLUM CURCULIO. 



Table CIII. — Results of spraying Georgia Belle peaches for the plum curculio, Myrtle, 

Ga., 1906 — Continued. 



Plat 

No. 


Treatment. 


Tree 
No. 


Fruit from 
grounds. 


Fruit from 
tree. 


Total 
num- 
ber of 
fruits. 


Total 
num- 
ber of 
fruits 

in- 
fested. 


Per- 
cent- 
age of 
sound 
fruit. 


Aver- 
age 
per- 


Total. 


In- 

ested. 


Total. 


In- 
fested. 


cent- 
age of 
sound 
fruit. 


III. 




1 
2 
3 

4 
5 

? 

8 
9 

10 

11 

. 12 


34 

29 
70 
69 
81 
28 
18 
14 
22 
16 
21 
17 


14 
22 
33 
33 
48 
16 
14 
11 
12 

6 
18 

9 


42 
25 
185 
224 
187 
98 
46 
75 
58 
80 
29 
75 


18 
17 
28 
52 
48 
26 
17 
20 
14 
6 
7 
11 


76 

54 

255 

293 

268 

126 

64 

89 

80 

96 

50 

92 


32 
39 
61 
85 
96 
42 
31 
31 
26 
12 
25 
20 


57.89 
27.77 
76.08 
70.98 
64.17 
66.66 
51.56 
65.16 
67.50 
87.50 
50.00 
78.26 












419 


236 


1,124 


264 


1,543 


500 




67.59 



Table CI V.- 



-Results of spraying Elberta peaches for the plum curculio, May field, Ga., 
. 1908. 



Plat 
No. 


Treatment. 


Tree 
No. 


Fruit from 
ground. 


Fruit from 
tree. 


Total 
num- 
ber of 
fruits. 


Total 
num- 
ber of 
fruits 

in- 
fested. 


Per- 
6ent- 
age of 
sound 
fruit. 


Aver- 
age 
per- 


Total. 


In- 
fested. 


Total. 


In- 
fested. 


cent- 
age of 
sound 
fruit. 


I 


Four applications, 2 pounds 
arsenate of lead plus 3 pounds 
stone lime per 50 gallons of wa- 
ter: Apr. 2, 11, 17, and 25. 

Three applications, 2 pounds 
arsenate of lead plus 3 pounds 
stone lime per 50 gallons of wa- 
ter: Apr. 2, 11, and 17. 

Two applications, 2 pounds ar- 
senate oi lead plus 3 pounds 
stone lime per 5C gallons water: 
Apr. 2 and 11. 


(1 

1! 

li 


156 
100 
194 


14 

11 

. 19 


336 
110 
437 


137 
32 
127 


492 
210 
631 


151 
43 
146 


69.31 
79.53 
76.86 






450 


44 


883 


296 


1,333 


340 




74.41 


II.... 


98 
188 
228 
.296 


12 

9 

18 

34 


322 
213 
361 
331 


137 
107 
140 
154 


420 
301 
589 
627 


149 
116 
158 
188 


64.52 
61.46 
73.18 
70.02 






810 

136 
135 
163 
61 


73 


1,227 


538 


2,037 


611 




70.00 


III... 


46 

16 

26 

3 


184 
299 
336 

145 


97 
38 
132 

45 


320 
434 

499- 
206 


143 
54 
158 

48 


55.31 
87.56 
68. 34 
76.70 






495 


91 


964 


312 


1,459 


403 




72.30 


rv... 


119 
86 

133 
85 

134 


87 
59 
39 
61 
82 


75 
10 
278 
125 
143 


64 
9 
197 
122 
126 


194 

96 

411 

210 

277 


151 
68 
236 
183 
208 


22.17 
29.17 
42.58 
12.86 
24.91 












557 


328 


631 


518 


1,188 


846 




28.78 



It will be noticed that on the unsprayed block only 28.78 per cent 
of the fruit was uninfested. Plat I, which received 4 applications of 
arsenate of lead, shows a gain in sound fruit of 45.63 per cent. Plat 
II, which received 3 applications, of 41.22 per cent, and Plat III, 
receiving 2 applications, a gain of 43.52 per cent. According to the 
notes accompanying this experiment very serious injury followed the 



SPEAYING PEACHES WITH AESENICALS. 



211 



4 applications given Plat I, and the injury to Plat III was also so 
severe as to render unsafe such a number of applications. 

Table CV gives results of spraying Elberta peaches for the curculio 
at Baldwin, Ga., in 1910. (See PI. XIX.) These plats contained 
some 200 trees each and counts were made of fruit produced through- 
out the season on 12 trees from each plat. Two applications of 
arsenate of lead were made, the first in water and the second in the 
self-boiled lime-sulphur wash (see p. 212). At the time of the first 
application, April 7-8, the blossoms of the trees had just fallen. The 
unsprayed block (Plat. II) yielded 56.85 per cent of sound fruit as 
compared with 89.85 per cent of sound fruit from the sprayed block, 
a gain of 33 per cent. 



Table CV. 



-Results of spraying Elberta -peaches for the plum curculio, Baldwin, Ga., 
1910. 



Plat 
No. 


Treatment. 


Tree 
No. 


Fruit from 
ground. 


Fruit from 
tree. 


Total 
num- 
ber of 
fruits. 


Total 
num- 
ber of 
fruits 

in- 
fested. 


Per- 
cent- 
age of 
sound 
fruit. 


Aver- 
age 
per- 


Total. 


In- 
fested. 


Total, 


In-' 
fested. 


cent- 
age of 
sound 
fruit. 


I 


First application Apr. 7-8, ar- 
senate of lead. 2 pounds to 50 
gallons water; second applica- 
tion, 2 pounds arsenate lead in 
self-boiled lime-sulphur wash 
(8-8-50), Apr. 27-28; third ap- 
plication, lime-sulphur wash 
only (8-8-50), June 17-18. 


f 1 
2 
3 
4 
5 

? 

8 
9 
10 
11 
. 12 

f 1 
2 
3 

4 
5 
6 
7 
8 
9 
10 
11 
12 


447 

119 

177 

363 

161 

96 

99 

222 

702 

224 

68 

348 


7 

8 

10 

24 

10 

12 

2 

22 

25 

6 

7 

17 


589 
465 
388 
606 
335 
409 
358 
293 
412 
476 
410 
456 


26 
45 
65 
76 
61 
26 
38 
33 
123 
83 
50 
58 


1,036 
584 
565 
969 
496 
505 
457 
515 

1,114 
700 
478 
804 


33 
53 
75 

100 
71 
38 
40 
55 

148 
89 
57 
75 


96.81 
90.92 
86.72 
88.63 
85.68 
92.47 
91.23 
89.32 
86.71 
87.28 
88.07 
90.67 






3,026 


150 


5,197 


684 


8,223 


834 




89.85 


n.... 


188 
187 
147 
839 

76 
605 
192 
318 

68 
143 
214 
274 


115 
83 
85 

114 
56 

165 
71 
55 
67 
67 

110 

100 


324 
385 
280 
648 
129 
471 
177 
299 
388 
176 
347 
283 


178 
132 
155 
239 

79 
189 

94 
147 
251 
137 
231 
168 


512 
572 
427 

1,487 
205 

1,076 
369 
617 
456 
319 
561 
557 


293 
215 
240 
353 
135 
354 
165 
202 
318 
204 
341 
268 


42.77 
62.41 
43.79 
76.26 
34.14 
67.10 
55.28 
67.26 
30.26 
36.05 
39.21 
51.88 












3,251 


1,088 


3,907 


2,000 


7,158 


3,088 




56.85 



The recent development, by Prof. W. M. Scott of the Bureau of 
Plant Industry of this department, of the self-boiled lime-sulphur 
wash as a fungicide for the control of brown rot and the scab of 
peach at once gave an enormous impetus to peach spraying. The 
desirability of combining arsenate of lead with the self-boiled lime- 
sulphur wash led to many tests to determine its practicability. Such 
a combination, while resulting' in important chemical changes, has 
in actual practice resulted in a spray which appears to be perfectly 
safe to peach foliage and fruit. Experience during the past 3 years 



212 THE PLUM CURCULIO. 

with this combined spray on peaches under varying climatic condi- 
tions seems to leave no doubt that by this combination the injurious 
properties of the arsenate of lead, as when used alone, are so reduced 
as to be practically negligible. This probably results from the ex- 
cess of lime in the self-boiled wash. In Circular 120 of this bureau, 
published in the spring of 1910, a schedule of applications for this 
combined spray was given, including 2 applications of arsenate of 
lead with an additional one of the lime-sulphur wash alone. This 
schedule was followed by many orchardists in the South and a large 
aggregate of trees was thus treated. The results have been uni- 
formly satisfactory, so far as controlling the curculio and the diseases 
are concerned, and without noticeable injury to the foliage and fruit 
above referred to. It may therefore be assumed that a satisfactory 
combined spray for the insect and the brown rot and scab of the 
peach has been established, as has so long been in use on other 
deciduous fruits. 

Results of further experiments with this combined spray for the 
curculio, brown rot, and scab during 1910 have been given in Far- 
mers' Bulletin 440, fully confirming previous results as to its great 
usefulness for the practical control of these three troubles. It is 
practically certain that its use will be equally effective in preventing 
losses to other stone fruits, as plums, cherries, apricots, etc. Direc- 
tions for making the self-boiled lime-sulphur wash and arsenate of 
lead spray, with a schedule of treatments for peaches, are quoted 
from the bulletin above referred to. 

DIRECTIONS FOR THE PREPARATION OF SELF-BOILED LIME-SULPHUR 

WASH. 

The standard self-boiled lime-sulphur mixture is composed of 8 
pounds of fresh stone lime and 8 pounds of sulphur to 50 gallons of 
water. In mild cases of brown rot and scab a weaker mixture con- 
taining 6 pounds of each ingredient to 50 gallons of water may be 
used with satisfactory results. The materials cost so little, how- 
ever, that one should not economize in this direction where a valu- 
able fruit crop is at stake. Any finely powdered sulphur (flowers, 
flour, or "commercial ground" sulphur) may be used in the prepa- 
ration of the mixture. 

In order to secure the best action from the lime, the mixture should 
be prepared in rather large quantities, at least enough for 200 gal- 
lons of spray, using 32 pounds of lime and 32 pounds of sulphur. 
The lime should be placed in a barrel and enough water (about 6 
gallons) poured on to almost cover it. As soon as the lime begins 
to slake the sulphur should be added, after first running it through 
a sieve to break up the lumps, if any are present. The mixture 
should be constantly stirred and more water (3 or 4 gallons) added 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate XIX. 




Fig. 1.— Gasoline Power Outfit in Operation. (Original.) 




Fig. 2.— Determining Results of Spraying, Each Peach Being Cut Open. (Original.) 

FIELD EXPERIMENTS IN GEORGIA FOR CONTROL OF PLUM CURCULIO 
AND PEACH DISEASES. 



SPRAYING PEACHES WITH ARSENICALS. 213 

as needed to form at first a thick paste and then gradually a thin 
paste. The lime will supply enough heat to boil the mixture sev- 
eral minutes. As soon as it is well slaked water should be added to 
cool the mixture and prevent further cooking. It is then ready to 
be strained into the spray tank, diluted, and applied. 

The stage at which cold water should be poured on to stop the 
cooking varies with different limes. Some limes are so sluggish in 
slaking that it is difficult to obtain enough heat from them to cook 
the mixture at all, while other limes become intensely hot on slaking, 
and care must be taken not to allow the boiling to proceed too far. 
If the mixture is allowed to remain hot for 15 or 20 minutes after 
the slaking is completed, the sulphur gradually goes into solution, 
combinirg with the lime to form sulphids, which are injurious to 
peach foliage. It is therefore very important, especially with hot 
lime, to cool the mixture quickly by adding a few buckets of water 
as soon as the lumps of lime have slaked down. The intense heat, 
violent boiling, and constant stirring result in a uniform mixture 
of finely divided sulphur and lime, with only a very small percentage 
of the sulphur in solution. The mixture should be strained to take 
out the coarse particles of lime, but the sulphur should be carefully 
worked through the strainer. 

DIRECTIONS FOR USING ARSENATE OF LEAD. 

Many experiments have shown that well-made arsenate of lead is 
much the safest of all arsenicals at present available for use on the peach. 
Arsenate of lead is to be found on the market both as a powder and 
as a putty-like paste, which latter must be worked free in water 
before it is added to the lime-sulphur mixture. The paste form of 
the poison is largely used at the rate of about 2 pounds to each 50 
gallons of the lime-sulphur wash and is added, after it has been well 
worked free in water, to the lime-sulphur spray previously prepared. 
As there are numerous brands of arsenate of lead upon the market, 
the grower should be careful to purchase from reliable firms. A 
decided change in color will result when the arsenate of lead is added 
to the lime-sulphur mixture, due to certain chemical changes which, 
in the experience of the writers, do not injuriously affect the fungi- 
cidal and insecticidal properties of the spray or result in important 
injury to the foliage. 

In large spraying operations it will be more convenient to prepare 
in advance a stock mixture of arsenate of lead, as follows: Place 100 
pounds of arsenate of lead in a barrel, with sufficient water to work 
into a thin paste, diluting finally with water to exactly 25 gallons. 
When thoroughly stirred, each gallon of the stock solution will thus 
contain 4 pounds of arsenate of lead, the amount necessary for 100 



214 THE PLUM CUBCULIO. 

gallons of spray. In smaller spraying operations the proper quantity 
of arsenate of lead may be weighed out as needed, and thinned with 
water. In all cases the arsenate of lead solution should be strained 
before or as it is poured into the spray tank. The necessary care 
should be exercised to keep the poison out of the reach of domestic 
and other animals. Powdered arsenate of lead is used at about one- 
half the strength of the paste form. 

SCHEDULE OF APPLICATIONS. 

Most of the peach orchards in the eastern half of the United States 
should be given the combined treatment for brown-rot, scab, and 
curculio. This is particularly true of the southern orchards, where 
all these troubles are prevalent. In some of the more northern 
orchards the curculio is not very troublesome, but as a rule it will 
probably pay to add the arsenate of lead in at least the first lime- 
sulphur application. 

The self-boiled lime-sulphur mixture referred to in the following 
outlines of treatment should be made of a strength of 8 pounds of 
lime and 8 pounds of sulphur to each 50 gallons of water, and the 
arsenate of lead should be used at the rate of 2 pounds to each 50 
gallons of the mixture or of water. When the poison is used in 
water there should be added the milk of lime made from slaking 2 
to 3 pounds of good stone lime. When used in the lime-sulphur 
mixture additional lime will not be necessary. 

Midseason varieties. — The midseason varieties of peaches, such as 
Reeves, Belle, Early Crawford, Elberta, Late Crawford, Chairs, 
Fox, and Beers Smock, should be sprayed as follows : 

(1) With arsenate of lead alone, about 10 days after the petals fall (PI. XX), or at the 
time the calyxes are shedding. 

(2) With self -boiled lime-sulphur and arsenate of lead, two weeks later, or four to 
five weeks after the petals have been shed. 

(3) With self-boiled lime-sulphur alone, four to five weeks before the fruit ripens. 

Late varieties. — The Salway, Heath, Bilyeu, and varieties with a 
similar ripening period should be given the same treatment prescribed 
for midseason varieties, with an additional treatment of self-boiled 
lime-sulphur alone, to be applied three or four weeks after the second 
application. 

Early varieties. — The Greensboro, Carman, Hiley, Mountain Rose, 
and varieties having the same ripening period should receive the first 
and second applications prescribed for midseason varieties. 

Where the curculio is not particularly bad, as in Connecticut, 
western New York, and Michigan, the first treatment, which is for 
this insecf only, may be omitted. Also for numerous orchards 
throughout the Middle States where the insect, especially in the 
younger orchards, is not yet very troublesome, orchardists should 



Bui. 103, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate XX. 




Size of Peaches at Time of First Spraying with Arsenate of Lead, Showing 
on the Left the Earliest and on the Right the Latest Stages in De- 
velopment when this Treatment Should be Given. (Original.) 



SPRAYING PLUMS AND CHERRIES. 215 

use their judgment as to whether the first application may be safely 
omitted. Where peach scab is the chief trouble, and brown-rot and 
curculio are of only minor importance, as may be the case in some of 
the Allegheny Mountain districts, satisfactory results may be had 
from two applications, namely, the first with self-boiled lime-sulphur 
and arsenate of lead four to five weeks after the petals fall, and the 
second treatment of the above schedule with self-boiled lime-sulphur 
alone three to four weeks later. These two treatments, if thoroughly 
applied, will control the scab and brown-rot, especially on the early 
and midseason varieties, and will materially reduce curculio injuries. 
Even one application of the combined spray made about five weeks 
after the petals fall would pay well, although this is recommended 
only for conditions where it is not feasible to do more. 

SPRAYING PLUMS AND CHERRIES. 

The first important tests of arsenicals in the control of the curculio 
were made on plums and cherries. In 1887 Mr. W. B. Alwood, work- 
ing under the direction of the entomologist of this department, made 
some limited tests on the grounds of the Ohio Agricultural Experi- 
ment Station, spraying Green Gage plum trees with Paris green at 
the rate of 1 pound to 50 gallons of water. Fully 50 per cent of the 
foliage and much of the fruit fell from the trees as a result of the 
treatment. No definite conclusions were drawn from the experiment. 
May 17 of the same year 17 cherry trees were also sprayed with Paris 
green, 1 pound to 50 gallons of water, and the results in this instance 
also were not fully determined. 

During the same year Prof. A. J. Cook in Michigan sprayed 4 plum 
trees May 18 with Paris green at the rate of 1 tablespoonful to 6 
gallons of water. No trees were kept for comparison, and no definite 
conclusions were thus to be drawn. During 1888 Prof. H. Osborn, 
then an agent of the Division of Entomology, carried out in Iowa 
some thorough spraying experiments, using 11 plum trees of several 
varieties, leaving 10 trees unsprayed as a check. London purple was 
used at the rate of one-half pound to 100 gallons, applications being 
made June 1 and 11. Concerning results, Prof. Osborn states: 

Combining the entire count of all varieties, and we have for the sprayed trees a 
final of 32.48 per cent punctured, or stung, and 5.71 per cent containing larvae, against 
a final of 41.86 per cent stung and 10.39 per cent containing larvae for the check trees. 

During the same year Prof. Weed in Ohio began a series of tests of 
arsenicals on cherry and plum, which were continued during 1889 
and 1890, during which latter year the work was carried out on a 
commercial basis in a plum orchard of 900 trees in the fruit districts 
along the south shore of Lake Erie. These careful experiments of 
Prof. Weed clearly showed that a considerable benefit from spraying 
was to be derived and were altogether the most extensive and com- 
plete heretofore presented. 



216 



THE PLUM CTJBCULIO. 



In Bulletin 9 of the Iowa Agricultural Experiment Station, page 
383 (1890), Prof. Gillette gives results of experiments on plums with 
London purple on the plum curculio and plum gouger. The poison 
was applied with a hand pump to 23 trees at the rate of 1 pound to 
120 gallons May 4 and 11. The leaves were badly burned. After 
May 25 all drop fruit on 5 trees each of the sprayed and unsprayed 
blocks was examined. A total of 21,000 plums was examined, and a 
benefit was determined of 1.1 per cent in favor of spraying. 



SOME RESULTS OF SPRAYING PLUMS. 

At Fort Valley, Ga., during 1905 Mr. Beattie carried out some spray- 
ing tests on Japanese plums. The plats were, however, small and 
there was considerable overflow from the surrounding unsprayed 
trees. Plats were laid off, extending across three varieties, namely, 
Wickson, Red June, and Satsuma, in which order the varieties are 
given in the table. The entire crop throughout the season from 
three trees of each variety was counted with the exception of Plat I, 
where only 2 trees were used. Plats received from 1 to 3 applications 
of arsenate of lead in water, without addition of lime. According to 
Mr. Beattie's notes practically no injury resulted to the foliage from 
the sprays. The results are given in Table CVI. 



Table CVI. 



-Results of spraying Japan plums for the plum curculio, Fort Valley, Ga., 
1905. 





Treatment. 


d 
H 


Fruit from 
ground. 


Fruit from tree. 


& 
ft 

£ 3 
o 

&H 


d 

a 
'3 

"3 
o 
Eh 


u 
,a 

si 

o 

Eh 


OJ 

a 

03 
O 

En 


0) 

'— t-l 

<!>*•-< 

fttf 

M3 
C3 o 
cu M 

> 
< 


ft . 

■sl 


Plat 
No. 


d 

1 

a 

3 

ft 


-d 

<D 

CI 
n 


d 

o 
to 


"3 
o 
Eh 


d 
3 

o 
ft 


d 
a 


T3 

a 
3 

o 

CO 


"3 
o 

&H 


o 

tu q 

5 ft 
S.*3 

■-t C 
i><3 
ft 


I 


One application, ar- 
senate of lead, 2 
pounds to 50 gal- 
lons water, Mar. 19. 

Two applications ar- 
senate of lead, 2 
pounds to 50 gal- 
lons water, Mar. 19 
and Apr. 20. 

Three applications 
arsenate of lead, 2 
pounds to 50 gal- 
lons water, Apr. 4 
and 20, May 4. 


1' 

1 

f 2 
3 

1 

r 2 

3 

fi 


52 

236 


44 
213 


2 
114 


54 
350 


152 

60 


37 

4 


26 
300 


178 
360 


204 
296 


81 
217 


28 
414 


232 
710 




















288 


257 


116 


404 


212 


41 


326 


538 


500 


298 


442 


942 


46.92 


39.41 


II.... 


255 
372 
210 


211 

345 
172 


71 
38 
32 


326 
410 
242 


430 
31 
73 


28 
11 
15 


527 
35 

200 


957 

66 

273 


685 
403 
283 


239 
356 
187 


598 

73 

232 


1,283 

. 476 

515 


























837 


728 


141 


978 


534 


54 


762 


1,296 


1,371 


782 


903 


2,274 


39.70 


41.20 


III... 


88 
153 
108 


69 
138 
92 


72 
65 
53 


160 
218 
161 


90 
90 
72 


25 

30 
8 


270 
194 
313 


360 
284 
385 


178 
243 
180 


94 
168 
100 


342 
259 
366 


520 
502 
546 


























349 


299 


190 


539 


252 


63 


777 


1,029 


601 


362 


967 


1,568 


61.67 


24.48 




68 
105 
72 


45 
87 
58 


31 
30 
10 


99 
135 
82 


40 
105 
118 


9 
17 
36 


35 
91 
6 


75 
196 
124 


108 
210 
190 


54 
104 
94 


66 

121 

16 


174 
331 
206 






IV... 




















245 


190 


71 


316 


263 


62 


132 


395 


508 


252 


203 


711 


28.55 


66.58 



SPRAYING PLUMS AND CHERRIES. 



217 



Curculio injury on all of the plats was severe. On the check there 
was only 28.55 per cent of fruit free from punctures and infestation. 
On the plat sprayed 3 times, 61.67 per cent of the plums were sound, 
a gain in sound fruit over the check of 33.12 per cent. Two applica- 
tions gave a gain of 11.15 per cent and the single treatment showed 
an increase over the check of 18.37 per cent, a difference doubtless 
due to location. A more exact idea of the commercial benefits of 
spraying, however, may be had by a consideration of the relative 
amount of ripe fruit at picking time showing the punctures of the 
insect, as being more or less deformed and unsalable, for it will be 
understood that not all ripe fruit showing punctures is unsalable. 
On the check plat (IV) of the ripe fruit at picking time 66.58 per cent 
were punctured, as against 24.48 per cent on Plat II, receiving 3 
applications. Plats I and II show about the same amount of punc- 
turing on the ripe fruit, namely, 39.41 and 41.20 per cent, respectively. 

During 1906, *t North East, Pa., an orchard of about two hundred 
16-year old plum (York State prune) trees were sprayed by Mr. 
Johnson, using Bordeaux mixture plus 3 pounds arsenate of lead. 
Through an error only one tree was left unsprayed for comparison. All 
of the fruit throughout the season was carefully examined from this 
tree and an adjacent unsprayed tree, and the results are shown in 
Table CVII. Previous to this season the owner had followed the 
jarring method, but by reason of the favorable results spraying was 
subsequently followed. 

This same orchard was sprayed during the following year by Mr. 
Johnson, and results taken on five sprayed and five unsprayed trees 
are shown also in the table. 

Table CVII.— Results of spraying York State prunes for the plum curculio during the 
seasons 1906 and 1907, North East, Pa. 













1906. 






















Fruit from ground. 


Fruit from tree. 


i 

a 
E'd 

£3 

C3 

O 

Eh 


h 


'3 


-t-3 

'g 


■a 

a 

3 


Trees. 


Treatment. 


d 

3 

O 


2 


•6 
O 


"3 

o 

EH 


T3 

| 
O 

a 

3 

Ph 


H3 

a 


■d 

o 

02 


"3 
o 

Eh 


"3 -a 

"3 
o 
Eh 


a 

3 
o 

"3 
o 
Eh 


a 
"3 

O 


a 

o 
hi 
a) 
Ph 


1 


Three treatments, 
Bordeaux mix- 
ture (4-4-50) plus 
3 pounds arsenate 
of lead: May 25, 
June 7 and 19. 


448 


393 


1,207 


1,655 


69 





1,640 


1,709 


517 


393 


2,847 


3,364 


84.63 




One untreated 


1,621 


1,446 


532 


2,153 


272 





470 


742 


1,893 


1,446 


1,002 


2,895 


34.61 













1907. 


















5 


Two applicat ions, 
Bordeaux mix- 
ture (4-4-50) plus 
3 pounds arsenate 
of lead: June 8 
and July 3. 


435 


344 


6,933 


7,368 


14 





9,559 


9,573 


449 


344 


16, 492 


16, 941 


97.35 




Five untreated 


581 


490 


7,481 


8,062 


57 





8,153 


8,210 


638 


490 


15, 634 


16,272 


96.08 



218 THE PLUM CURCULIO. 

During 1906 there was a gain in sound fruit on the sprayed trees 
of 50.02 per cent as compared with the check of 50.01 per cent. The 
difference the following year, however, was small, 1.27 per cent, as 
the insects were comparatively scarce, no doubt following their 
practical extermination in the orchard the year previous. 

Extensive plum-spraying experiments were begun at Barnesville, 
Ga., in 1910. The work, however, was stopped by the loss of practi- 
cally all of the fruit from the effects of a heavy wind storm. 

RESULTS OF SPRAYING CHERRIES. 

A block of Montmorency cherry trees at North East, Pa., was 
sprayed June 11 with 3 pounds of arsenate of lead to 50 gallons of 
water plus 3 pounds of stone lime. Another block received an addi- 
tional application June 25, while a third block (4 rows through center 
of orchard) was left unsprayed. When fruit was gathered, July 18, 
three trees on the first-mentioned plat gave a total of 16 wormy 
cherries and 43^ pounds of sound fruit. The same number of trees on 
the second block, having 2 applications, gave 10 wormy cherries 
and 53 pounds of sound fruit. The 3 trees on the check plat gave 74 
wormy cherries and only 16 pounds of sound fruit. The trees were 
chosen as nearly alike as possible and the results may thus be fairly 
compared. As compared with the check, the plat treated twice 
shows an increase in sound fruit of 37 pounds and from the plat 
sprayed once a gain of 27.5 pounds. 

More data are needed to show the protection from curculio which 
will follow spraying plums and cherries, though this will without 
doubt be quite as marked as with peaches. The same spraying 
schedule indicated for early peaches will be suitable for plums and 
cherries, and the arsenical should be used in the self-boiled lime- 
sulphur wash. 



ECONOMIC BIBLIOGRAPHY. 1 

1736-7. Collinson and Bartram. — Darlington's Memorials of Bartram and Mar- 
shall, p. 85. 

Remedy for insect that annoys plums, apricots, and nectarines. 

Id — p. 93. 

An account of the destruction by an insect of plums and nectarines. 
Id.— p. 120. 

Advice against the planting of sloes, as they are "liable to be bitten with the 
same insect as the rest of our stone fruits." 

1749. Kalm, Peter. — Travels into North America. <Foster's English Translation, 
2nd Edition, London, 1772, p. 44,vol. 2. 

Under date of May 18, 1849, writing of New Jersey: "The grass in the meadows 
is likewise consumed by a kind of worms, and other species cause the plums to 
drop, before they are half ripe." 

1302. Burton, Benj. Smith, M. D. — On the Natural History of North America. 
Letter to M. Lacepede of Paris. Philadelphia, October 31, 1802. <In 
Philosoph. Mag., vol. 22, p. 204, 1805. 

"The unripe fruit of the peach is greatly injured by a species of curculio; but 
the insects most pernicious to this tree are two Lepidopterous insects of the genus 
Xygaena Fabr. These while in the larval state destroy the bark of the root." 
Footnote, p. 208. 

1804. Tilton, James. — Curculio. <Willich's Domestic Encyclopaedia, vol. 3, p. 116, 
1804. 2. Extr. Papers on Agr., vol. 2, pp. 15-19, 1809. 

Probably earliest extended account of the plum curculio. 

1806. Melsheimer, Fred. Val. — Catalogue of Insects of Pennsylvania, p. 28, No. 

589. 

Lists as Curculio persicse, and states, lives in Malus persica, the larva under bark. 

1807. Olivier. — Histoire Naturelle des Insectes, vol. 5, p. 19, 1807. 

1807. Tilton, James. — Memoirs of the Philadelphia Society for Promoting Agricul- 
ture, vol. 1, pp. 34-38, Appendix. 

Several correct facts about the feeding habits of the curculio, its mode of propa- 
gation, and points in its life history, with various recommendations for control. 

1815. Tilton, James. — Memoirs of the Philadelphia Society for Promoting Agricul- 
ture, vol. 1, p. 192. 

Letter from Dr. Tilton to Richard Peters, esq., dated Nov. 16, 1807. Mentions 
destructiveness of curculio to peaches, and includes extended account of this 
insect. 

1819. Peck, W. D. — Insects which affect oaks and cherries. <Memoirs Agr. Soc. 
Mass., Agr. Journ., 1819, p. 312. 

Description of curculio as Khynchxnus cerasi, with figure of beetle. 
1819. Muse, Joseph E. — Entomology. <American Farmer, vol. 1, no. 16, pp. 124- 
125, July 16. ' 

Account of observations and experiments. 
1822. Thacher, Dr. James. — The American Orchardist, p. 109. 

An extract from Domestic Encyclopaedia. Article by Dr. James Tilton, Wil- 
mington, Del. Gives principal points in life history of the plum curculio and 
mentions several remedies. 

1 Titles marked by asterisk (*) have not been verified. 

219 



220 THE PLUM CURCULIO. 

1824. Mitchell, Samuel L. — American Farmer, vol. 6, no. 23, p. 183. 
An early systematic account of the curculio. 

1826. Harris, Thaddeus Wm. — New England Farmer, vol. 5, pp. 169-171, Decem- 
ber 22. 

Remarks on the plum curculio. 

1828. "Scrutator." — New England Farmer, vol. 7, pp. 81-82. 

Brief description of the curculio, with remarks on its feeding habits, and methods 
of propagation. 

1828. Harris, Thaddeus Wm. — The curculio, or worm, in fruit. <New England 

Farmer, vol. 7, pp. 81-82, October 3. 

1829. "J. K."— American Farmer, vol. 2, no. 18, p. 140. 

An account of the feeding habits of the curculio; also stated that, in addition to 
destroying the plum, peach, apricot, and nectarine, it is frequently found on the 
apple. 

1829. Prince, Wm. — A short treatise on horticulture (1828), p. 22. 

Recommends paving around trees as far as branches extend as a means to exter- 
minate the plum curculio. 

1829. "J. K."— American Farmer, vol. 9, no. 18, p. 140. 

Remarks on the puncturing of fruit by the curculio. 

1830. "Anonymous letter to a gentleman of Philadelphia." — American Farmer, 

vol. 12, No. 34, p. 267. 

Description of the plum curculio, written to compete for a premium offered by 
the Pennsylvania and the Massachusetts Horticultural Societies. 

1830. Reynolds, S. — American Farmer, vol. 12, no. 23, p. 179. 

Recommends wood ashes and lye drenched around the trunks of infested trees 
as remedy against plum curculio. 

1830. Hildreth, S. P. — New England Farmer, vol. 9, p. 82. 

Complaint of the destruction of all stone fruits by the curculio, and encourages 
the offering of a premium for an effective remedy. 

1831. Wilson, Wm. — American Farmer, vol. 12, no. 49, p. 389. 
* Description of the curculio. 

1832. Manly, B. — New Genesee Farmer, vol. 2, pp. 45-53; id., pp. 62-63. 

Description of the curculio and reference to remedies. 

1838. Lewis, G. M.— The Cultivator, vol. 5, no. 6, p. 111. 

Recommends paving around infested trees as the most effective remedy for the 
curculio. 

1838. Manning, Robert. — Book of fruits, p. 33. 

Refers to growing stone fruits by the sea, as the curculio are said to avoid the 
salt air. 

1838. Briggs, L. W.— New England Farmer, vol. 16, p. 389. 

Recommends use of tin troughs around trees and filled with water and lamp oil 
to prevent ascent of tree by the curculio. 

1840. Burnett, Joel. — New England Farmer, vol. 18, p. 304. 

Recommends jarring infested trees twice a day as long as the insects are in evi- 
dence and collecting dislodged curculios on sheets placed beneath the trees. 

1841. Harris, Thaddeus Wm. — Plum tree grubs. <New England Farmer, vol. 19, 

p. 405. Figure. 

Brief treatment against grub of plum curculio. 

Id. — Insects Injurious to Vegetation (1st ed.), pp. 67-69. 
Good general account of the plum curculio. 

1842. Thacher, James. — The Southern Agriculturist, vol. 2, no. 1, p. 47. 

Remedy: Spreading under infested trees lime, wood ashes, fresh seaweed, ground 
bark from tan pits, coal ashes, etc., to prevent descent into the earth of the cur- 
culio. 

1843. Harris, Thaddeus Wm. — Apple worm; curculio plum grub. <New England 

Farmer, vol. 22, p. 13. 

Characteristics of codling moth and curcgio. 



ECONOMIC BIBLIOGRAPHY. 221 

1843. Burnett, Joel. — Trans. Mass. Hort. Soc, 1843, p. 18. 

Resume^ of the early accounts of the curculio and methods for its control. 

1843. Lovett, Capt— The Cultivator, vol. 10, no. 9, p. 150. 

The plum curculio killed by salt. 

1844.* Gaylord, W.— Trans. N. Y. St. Agr. Soc, vol. 3, pp. 314-315. 

Prize essay on plum curculio; compiled account of life history, etc. 

1844. Kenrick, John A. — The New York Farmer and Mechanic, vol. 1, no. 21, 

p. 347. 

Remedy against plum curculio: Batter of meadow mud well saturated with 
salt lye spread and spaded to each infested tree. 
1844. Jacobs, Benjamin.— The New York Farmer and Mechanic, vol. 2, no. 17, 
p. 271. 

Salt spread over the ground under plum trees as far as spread of limbs prevents 
curculio arising from ground in early spring, and insures abundant crop of fruit. 
1844. Harris, T. W — New England Farmer, vol. 22, p. 13. 

Description of the grub of the plum curculio; distinguished from the apple 
worm. 
1844. Burnett, Joel. — New England Farmer, vol. 22, pp. 49-51. 

Description of the curculio with/"~"res of the various stages; life history obser- 
vations, and methods to be employed for its control. (An essay to compete for an 
award of $200 for destroying the curculio, offered by the Massachusetts Horticul- 
tural Society.) 
1847. Landreth, D. — Dictionary of Modern Gardening, p. 176. 

Quotes article from " Fruits and fruit trees of North America," by Downing. 

1847. Davis, N. S. — Fruits, Insects, etc.<Amer. Journ. Agr. and Sci., vol. 5, pp. 

168-169, March. 

Injuries produced by the plum curculio discussed. 

1848. Hall, Caleb.— The Cultivator, vol. 5, no. 9, p. 278. 

Fumigating plum trees with brimstone to protect from ravages of the curculio 
recommended. 

1849. Cole, S. W.— American Fruit Book, p. 204. 

An account of the plum curculio, with description and figures of larva, pupa, and 
adult, and stung plum. Treats of remedies. 
1849. Cleveland, H. W. S— The Horticulturist, vol. 4, no. 3, p. 128. 

An account of paving under infested trees to protect crop of fruit from plum 
curculio. 

1849. Spalding, L. A.— The Cultivator, vol. 6, no. 8, p. 247. 

An article "Paving vs. Jarring" in treatment against plum curculio. 

1849. Sanborn, Eastburn. — New England Farmer, vol. 1, no. 9, p. 137. 

An account of breeding experiments to determine habits of the curculio; reme- 
dial measures indicated. 

1850. Harwell, Robert. — The Horticulturist, vol. 5, no. 6, p. 258. 

An account of puncturing of fruit by the curculio. 

1850. Gabriel, G. — The Horticulturist, vol. 5, no. 1, p. 22. 

Remarks on remedies against plum curculio, namely, gouging eggs out with sharp 
instrument. 

1850. Spalding, L. A. — The Horticulturist, vol. 5, no. 1, p. 30. 
An account of paving to destroy the curculio. 

1850. Young, L. — The Horticulturist, vol. 5, no. 5, p. 245. 

Whitewashing trees and dusting with lime to prevent curculio injury. 

1850. Cole, S. W.— The Cultivator, vol. 7, no. 12, p. 395. 
Remarks on jarring against the plum curculio. 

1850* Moulson, S. — New England Farmer, vol. 2, no. 24. 
Account of the destructiveness of the curculio. 

1850. Drake, R. H— The Cultivator, n. s., vol. 7, p. 47. 
Remarks on jarring against the plum curculio. 

1850. Sanborn, Eastman. — New England Farmer, vol. 2, no. 12, p. 197. 
Account of plum curculio and remarks on remedies. 




222 THE PLUM CURCULIO. 

1850. Simpson, H. B — The Southern Planter, vol. 10, no. 9, p. 265. (From Hovey's 
Magazine of Horticulture.) 

An account of the habits of the curculio with remedial measures for its control. 
1850. Drake, R. H. — The Cultivator, vol. 7, no. 1, p. 47. 

Remarks on jarring against the plum curculio. (Uses a large umbrella to catch 
falling insects.) 

1850. Harris, Thaddeus Wm. — Injurious insects. <New England Farmer, vol. 2, 

p. 252. 

Habits and ravages of the plum curculio, with remedies. 
1850.* H(arris), T. W. — Curious facts in natural history. <Sat. Rambler, vol. 5, no. 
47, p. 4, November 23. 

Remarks on the plum curculio. 

1851. Green, Harvey. — The Genesee Farmer, vol. 12, p. 96. 

An account of destroying the curculio by holding burning straw torches around 
infested trees, into which the beetles fly. 

1852. Hackett, J. — The Horticulturist, vol. 7, no. 1, p. 51. 

An account of freeing trees from curculio by throwing common wood ashes all 
through the branches and over the tree early in the morning when wet with dew. 
1852. Stokes, Wm.— The Horticulturist, vol. 7, no. 8, p. 350. 

Results of spraying trees with whitewash to which has been added flour of 
sulphur, at the rate of one-half pound to a pailful of whitewash. 
1852. Buchanan, R. — The Horticulturist, vol. 7, no. 9, p. 438. 

Reports good results by the shaking system and details the methods .for its 
operation against the plum curculio. 
1852. Ludlow, Thos. W., Jr.— The Horticulturist, vol. 7, no. 9, p. 432. 

Ravages of the curculio prevented. 
1852. Dean, Joshua. — The Horticulturist, vol. 7, no. 11, p. 528. 

"Remedies for the curculio. A new one." (An ounce of sal ammoniac and a 
pint of soft soap dissolved in 3 gallons of water, thrown on the foliage and fruit 
with a syringe in the morning, twice or thrice a week.) 
1852. "C. E. G."— The Cultivator, vol. 9, n. s., no. 4, pp. 146-147. 

Plan of a curculio catcher. Facts and figures showing that the curculio can be 
certainly, safely, and cheaply resisted. 
1852. Birmingham, H. — The Cultivator, vol. 9, n. s., no. 5, p. 182. 
Oil troughs for the curculio. 

1852. Evans, Gurdon. — Insects injurious to vegetation. In a general view and 

agricultural survey of Madison Co., N. Y.<Trans. N. Y. St. Agr. Soc, vol. 
11, pp. 745-746, 1851. 

1853. Betts, Chas. — The Cultivator, vol. 1, no. 5, p. 155. 

Throwing air-slaked lime into plum trees to prevent curculio injury. 

1853. Maxwell, S., Jr.— The New England Farmer, vol. 5, p. 372. 

Discovers eggs of curculio under flap, which he regards as new habit in history 
of insect. Recommends removal of egg with penknife.- 

1853. Lake, J. — New England Farmer, vol. 5, p. 479. 

Uses air-slaked lime on trees when fruit sets, applying early in the morning when 
dew is on. Reports complete success. 

1854. Parsons, John, Jr. — American Agriculturist, vol. 13, no. 8, n. b., p. 118. 

An account of jarring plan, giving details of the work and indicating number of 
beetles caught during different years, and amount of sound fruit at harvest time. 

1854. Longworth, N. — The Country Gentleman, vol. 3, no. 4, p. 59. 

Saves his crop from plum curculio by paving under trees as far as spread of 
branches. 

1854. Downing, A. J. — Rural Essays, p. 439. 

Remarks on destructiveness of curculio to plum; and states it is less injurious 
where soil is a stiff fat clay, where curculio finds poor quarters in the soil. 

1854. Robinet, A. — New England Farmer, vol. 6, p. 325. 

Quotes Ohio Cultivator; communication to Cincinnati Horticultural Society, 
Recommends jarring against plum curculio, using two semicircular sheets on hoop 
frames. 



ECONOMIC BIBLIOGRAPHY. 223 

Clement, Asa. — New England Farmer, vol. 6, p. 234. 

Describes jarring against plum curculio and recommends use of sheet. 

Hadley, Joseph. — New England Farmer, vol. 6, p. 315. 

Use of putrid soap suds against plum curculio, followed by dusting with lime. 

Chapin, Rubin. — New York Tribune. 

Quotes New England Farmer, vol. 6, p. 210. Describes remedy used by J. H. 
Mather, namely, sulphur, lard, and Scotch snuff, mixed and rubbed freely on body 
and branches of trees. In a few days curculio all left. 

Harris, T. W. — Report on some of the diseases and insects affecting fruit 
trees and vines. <Troc. Amer. Pom. Soc, p. 215. Sep.: Boston, 11 pp. 
Rept. Journ. U. S. Agr. Soc. pp. 197-210. Amer. Pom. Soc, 1854. 

Wyman, J. P. — New England Farmer, vol. 7, p. 374. 
Describes injury of curculio to apple. 

Holmes, S. N. — The Country Gentleman, vol. 7, no. 24, p. 383. 
Fumigation with tobacco fumes to prevent curculio attack. 

Hill, Dr. — The Country Gentleman, vol. 7, no. 26, p. 412. 
Experiments t„ determine migratory habits of curculio. 

Pinney, A. — The Genesee Farmer, vol. I, , 2d ser., p. 283. 
Remarks on habits of plum curculio, as a peach pest. 

Thomas, J. J. — The Country Gentleman, vol. 8, no. 8, p. 142. 

Mathew's curculio remedy. Refers to remedies in vogue. 

Kirkpatrick, John. — Notes on a few insects of northern Ohio, injurious to 
the farmer or horticulturist. <10th Ann. Rept. Bd. Agr. Ohio, 1855, pp. 
243-244. 

Includes remarks on the plum curculio. 

Lothrop, D. W. — The Genesee Farmer, vol. 18, 2d ser., p. 286. 

Remarks on various remedies against the plum curculio, such as paving, shaking, 
and syringing the trees with asafcetida, salt water, and strong limewater. 

Fowler, Samuel P. — Distribution of insects injurious to vegetation. <4th 
Ann. Rept. Sec. Mass. Bd. Agr., 1856, pp. 449-450. 

Habits and means to be used against the plum curculio. 

Darling, Mrs. N. — New England Farmer, vol. 10, p. 73. 
Questions raised as to life history of the plum curculio. 

White, W. N. — American Agriculturist, vol. 17, no. 8, n. s., p. 245. 
Discussion of the shaking method to protect fruit against curculio. 

Clay, C. M. — The Country Gentleman, vol. 12, no. 1, p. 14. 
Remarks on various curculio remedies. 

Affleck, Thomas. — The Country Gentleman, vol. 12, no. 17, p. 272. 

Refers to the discovery by an intelligent citizen of a new remedy for the curculio, 
to be given to the public for some compensation, and makes inquiry about prem- 
iums offered by some of the eastern horticultural societies. 

Ludlow, Thos. W., Jr. — The Country Gentleman, vol. 12, no. 10, p. 158. 

Remarks on habits of the curculio and remedies for protecting fruit against its 
depredations. 

Sanborn, Francis Gregory. — Entomology. <5th Ann. Rept. Sec. Mass. 
Bd. Agr., 1857, p. 199. 

Characters and habits of the plum curculio, and remedies. 

Logan, D. B. — The Cultivator, vol. 7, 3d series, no. 3, p. 82. 

Remarks on remedy against the plum curculio, namely, whale-oil soap syringed 
on infested plum trees. 

Fitch, Asa. — The Cultivator, vol. 7, 3d series, no. 11, p. 340. 

Parasitic enemies of the curculio. Food habits. Describes and figures Sigalphus 
curculionis Fitch, with notes on its habits. 



224 THE PLUM CURCULIO. 

1859. Morris, Miss Margareta H. — Original observations on insects injurious to 

our fruits. The Curculio.<Horticulturist, vol. 14, pp. 506-508, pi., and 
figs. 1-4. 

Characters and natural history of the plum curculio. 

1860. Goodrich, Chauncey E. — The Country Gentleman, vol. 15, no. 21 (whole 

no. 385), p. 334. 

The curculio and its repulsion; its natural history and its habits; remedies. 

1860. Fitch, Asa. — "Address." On the curculio and blackknot of plum trees. 

<Trans. N. Y. State Agr. Soc, 1859, vol. 19, pp. 599-612. Separate: Albany, 
1860, pp. 15-28. 

Description, ravages, and parasite of the plum curculio, and remedies. 

1861. Walsh, Benjamin Dann. — Insects injurious to vegetation in Illinois. <Trans. 

111. St. Agr. Soc, vol. 4, pp. 345-346, September. Separate: 1861, 43 pp. 
Repr. (partim), Trans. 111. Nat. Hist. Soc, vol. 1; Prairie Farmer, December 
6, pp. 370-371. 

Notes on the plum curculio. 

1863. Id. — The plum gouger; a new foe of the plum.<Prairie Farmer, vol. 27, n. s. 

vol. 11, pp.. 372-373, figs., June 13. 

Compares Anthonomus with Conotrachelus. 

1864. Id. — The. four-humped curculio. A new foe of the apple. <Valley Farmer. 

Rept. Prairie Farmer, vol. 30, n. s., p. 131, 2 figs., August 27. 
Compares with nenuphar. 

1864. Trimble, I. P. — Injurious insects. <Proc Amer. Pom. Soc, pp. 93-94. 

Habits of the plum curculio. 

1865. Id. — A treatise on the insect enemies of fruit and fruit trees. New York, 

11 pis., pp. 3-102. 

An extended account of curculio and codling moth, with numerous colored plates. 

1865. Sanborn, Francis Gregory. — The habits of insects in their relation to 
man.<12th Ann. Rept. Sec. Mass. Bd. Agr., 1864, p. 158. 

Ravages of the plum curculio. 

1865. Riley, C. V. — Flea-beetles and curculio. <Prairie Farmer, vol. 31, n. s. vol. 
15, p. 418, fig. 

Habits of the plum curculio and remedies; figures pupa. 

1865. Walsh, B. D. — On phytophagic varieties and phytophagic species with 
remarks on the unity of coloration in insects. <Proc Ent. Soc. Phila., vol. 5, 
p. 207, Ann. (and Mag.) Nat. Hist., vol. 16, ser. 3, pp. 383-384. 

Refers to curculio. 

1865. Masten, C. R. C. — The Cultivator and Country Gentleman, vol. 27, no. 693, 

p. 271. 

Remarks on habits of the curculio. 

1866. Walsh, B. D.— Doctors differ. <Pract. Ent., vol. 1, p. 96, July 30. Criti- 

cisms; sheep in orchard do not keep away nenuphar. Answer to the above 
by B. D. W., ib., vol. 2, pp. 31-33, figs. Answer to questions in S. S. 
Houghton's Insects in the Orchard (ib., pp. 30-31). 
Food habits and hibernation of the plum curculio. 

1866. Riley, C. V. — Black-knot once more.<Gardener's Monthly and Horticulture, 
vol. 8, pp. 331-332, November. 

Larvae present in swellings of (Sphseria) Plowrightia morbosa Sacc. 

1866. Houghton, J. S. — Insects in the orchard. <Pract. Ent., Dec, vol. 2, pp. 30-31. 
Notes on the plum curculio. 

1866. Brackett, G. F. — Practical Entomology No. 10.<Maine Farmer, July 19. 

Description of the plum curculio and means to be taken against it. 

1867. Trimble, Isaac P. — An insect talk.<Amer. Pom. Soc, pp. 119-120. 

Habits of the plum curculio and means to be taken against it. 



ECONOMIC BIBLIOGRAPHY. 225 

1867. Riley, 0. V.— The curculio.<Prairie Farmer, vol. 35, n. s. vol. 19, p. 381. 

Successful use of machines for destroying the plum curculio; hibernates as adult. 
Id.— vol. 36, n. s. vol. 20, p. 148. 

Answer to inquiry regarding plum curculio; means to be taken against same. 
Id.— vol. 39, n. s. vol. 23, p. 122. 

Answer to inquiry regarding plum curculio; habits and means to be taken 
against same. 

1867. Hill, Franklin C. — The little Turk and its crescent. <Pract. Ent., August- 
September, vol. 2, pp. 114-115. 

Oviposition of the plum curculio. 

1867. Walsh, B. D. — Means against curculio: (Estridse.<Pract. Ent., vol. 2, p. 97. 

Answer to inquiry regarding the plum curculio; ineffective remedies against 
same. 
Id— pp. 75-81. 

Characters of the Rhynchophora, with injuries, life history, food habits, num- 
ber of generations, and remedies. 

Id. — p. 71. Extr. from Genesee Farmer, 1853, p. 125. Fighting the cur- 
culio. 

Ridicules recommendation of re 7 " " lies other than jarring against plum curculio. 

Id. — Prairie Farmer, vol. 36, n. s. vol. 20, p. 359. 
Ravages and means against. 

Id.— Pract. Ent., vol. 2, pp. 114-115. 

Comments on correspondence; oviposition of plum curculio. 

Id. — First annual report on the noxious insects of the State of Illinois. <Trans. 
111. St. Hort. Soc, 1867, n. s., vol. 1, Appendix, pp. 64-72. Separate: Chi- 
cago, 1868, figs. 

History, generations, enemies of the plum curculio, and remedies. 

1868. Harris, Thaddeus Wm. — Insects injurious to vegetation (3d edition), pp. 

75-82. 

1868. Riley, C. V. — Report of committee on entomology. <Trans. 111. St. Hort. Soc, 
1867, n. s., vol. 1, pp. 112-114. 

Habits and food plants of the plum curculio, and injuries inflicted by same. 

1868. Walsh, B. D. — The bug-hunter in Egypt. A journal of an entomological 
tour into south Illinois by the senior editor. <Amer. Ent., vol: 1, pp. 11-14, 
figs. 
Id.— pp. 33-36. 

Predaceous enemies of the curculio. 

Id. — The six worst insect enemies of the fruit growers in northern Illinois.' 
<Trans. 111. Hort. Soc, 1867-68, p. 94. 

1868. Walsh, B. D., and Riley, C. V.— Hogs vs. bugs.<Amer. Ent., vol. 1, pp. 3-6. 
Swine as enemies of the plum curculio; favorable quotations. 

Id. — Entomological quackery. <Amer. Ent., vol. 1, p. 56. Rept. of "The 
Curculio," Iowa Homestead, July 22, 1868. 

Comments on the plum curculio; means against same. 

1868. Walsh, B. D., and Riley, C. V. — Curculio and barklice.<Amer. Ent., vol. 1, 

p. 80. 

Reply to inquiry regarding plum curculio; hibernation of same. 

Id. — p. 241. Comparative scarcity of the curculio again. 
Observations during summer of 1869. 

1869. Riley, C. V. — 1st Ann. Rept. on noxious insects, etc., of the State of Missouri. 

<4th Ann. Rept. St. Bd. Agr., 1868, pp. 50-52, 6 figs. 
Excellent account of plum curculio and resume^. 

17262°— Bull. 103—12 15 



226 THE PLUM CTJRCULIO. 

1869.* Riley, C. V.— Prairie Farmer, July 10, vol. 40, n. s. vol. 24, p. 218, fig. 

Apple leaf crumpler mistaken for curculio. Correspondence: Improper use of 
the word Curculio; means against. Figs. 

Id.*— 

Reply: Recommends jarring against plum curculio. 
1869. Walsh, B. D., and Riley, C. V. — Plums for the million. <Amer. Ent., vol. 1, 

pp. 92-93. 

Remedies. Varieties of plums exempt from attack by plum curculio. 

Id. — p. 161. Curculio remedies. 

Comments on an essay on the plum; coal oil not effective against plum curculio. 

Id. — p. 183. Another new curculio humbug. 

Extract from an agricultural paper, with criticisms. 

Id. — p. 202. The curculio scarcer than last year. 

Excerpt from correspondence; comparative scarcity of the curculio in 1869. 

/^_ — pp. 217-218. Is the curculio scarcer than it was last year? 
Observations to prove it so. 

Id. — p. 226. A new curculio humbug. 

Reply: Usefulness of a patented lamp. 

1869. "G. G." — Hogs vs. Curculio. <Rural New Yorker, August 28. Reprint: 
Amer. Ent., vol. 2, p. 56, November. 

Usefulness of hogs against plum curculio. 

1869. Francis, Lucius O. — Curculio remedies. <Amer. Ent., vol. 1, p. 161. 

1869. Brown, A. M.— Curculio notes.<Amer. Ent., vol. 1, pp. 239-241. 
Habits and natural history of the plum curculio. 

1869. Bayler, John C— The plum curculio. < Amer. Ent., vol. 2, p. 53. 

1870. Trimble, Isaac P.— The plum curculio will deposit in fruit which overhangs 

water.<Amer. Ent., vol. 2, pp. 119-120. 

Tests and arguments to prove that trees planted over water are not protected 
from attacks of the plum curculio. 

1870. Pullen, B. — Hindrances to successful fruit growing. <Amer. Ent. and Bot., 
vol. 2, p. 170. 

Remedies against plum curculio. 

1870. Le Baron, W.— Prairie Farmer, vol. 41, p. 338, October 29. 
Habits of the plum curculio. 

Id.— p. 258. 

Character and habits of the plum curculio. 

1870. Hartwell, J. B. — Notes from Wilkinson ville, Mass.<Amer. Ent. and Bot., 
vol. 2, p. 336. 

Injuries inflicted by plum curculio. 

1870. Riley, C. V. — The plum curculio (Conotrachelus nenuphar Herbst.).<Amer. 
Ent., vol. 2, pp. 130-137, fig. 92. 

Summary of knowledge concerning the plum curculio, with discussion of dis- 
puted points. 

Id. — p. 165. Is any knowledge useless? 

Reprint of an article in Manufacturer & Builder, November, 1869. Cases in 
which knowledge of minute scientific facts will be of great value. 

Id. — pp. 225-227. Notice: Cultivator and Country Gentleman, vol. 35, pp. 
360-361. Great discovery. Curculio extermination possible! 

Reprint of articles on destruction of curculio; criticisms; remedies, etc. 

Id. — The new curculio remedy, p. 243. 

Id. — p. 276. The plum curculio breeds in apple. 

Reply to correspondent regarding the plum curculio. 



ECONOMIC BIBLIOGKAPHY. 227 

1870. Riley, C. V.— The Ransom curculio remedy. <Amer. Ent., vol. 2, pp. 268-271. 

Efficiency of the "Ransom chip-trap against the plum curculio"; criticism of 
articles on this subject. 

Id. — pp. 338. Paris green for the curculio. 

Paris green ineffective against the plum curculio. 

1871. Saunders, W. — Hints to fruit growers. Paper No. l.<Can. Ent., vol. 3, p. 12. 

Remedies against the plum curculio. 

1871.* Reed, E. B. — Insects affecting the plum.<Rept. Fruit Growers' Assn. 
Ontario, 1870, pp. 120-126, 7 figs. 

Characters and habits of the plum curculio, and remedies against same. 
1871. Le Baron, W. — The plum curculio and the plum gouger, striped grapevine 
caterpillar. .Notes to correspondents. <Prairie Farmer, vol. 42, p. 171, 
June 3. 

Habits of the plum curculio. 

1871. LeBaron, W. — Insects injurious to fruits. <Trans. North. 111. Hort. Soc, 

pp. 85-89. 

Brief notes on the plum curculio. 

1871. Glover, Townend. — Report of the Entomologist and curator of the museum. 
<Rept. U. S. Comm. Agr. for 1870, pp. 68-70. 
Brief note on the plum curculio. 

1871. Riley, C. V. — Third Annual Report on the noxious, beneficial, and other 
insects of the State of Missouri. <6th Ann. Rept. St. Bd. Agr. f. 1870, pp. 11- 
29, 9 figs. Separate: Jefferson City, Mo., April, 1871. 

Details in life history of the plum curculio and means of control. 

1871. Saunders, W. — Hints to fruit growers. Paper No. 2.<Can. Ent., vol. 3, p. 26, 

1 fig. 

Remedies against the plum curculio. 

1872.* LeBaron, W. — Southern Illinois curculio experiments. <Prairie Farmer, 
June 15. 

Notes on hibernation of the plum curculio and remedies against same. 

1872. Meehan, T. — Insects on cherry trees. <Gardener's Monthly, vol. 14, n. s. vol. 5, 

p. 154. 

Remedies against the plum curculio. 

1872. Glover, Townend. — Report of the entomologist and curator of the Museum. 
<Rept. U. S. Comm. Agr. f. 1871, p. 77. 
Remedies against the plum curculio. 

1872. Wier, D. B. — Insects most noxious to fruit growers. <Trans. Wise. St. Hort. 
Soc. f. 1872, pp. 165-167, 1 fig. 

Includes and deals with curculio. 

1872. Riley, C. V. — Einige unserer schadlicherer Insekten, St. Louis, pp. 18-26, 

5 figs. 

Descriptions and figures of the plum curculio; habits, injuries, parasites, ene- 
mies, and remedies. 

Id.— Economic entomology. <Trans. Kans. St. Bd. Agr., 1872, pp. 320-323, 

2 figs. 

A chapter on curculio. 

1873. Id* — Curculio on pears. <I11. Journ. Agr. 

Habits and history of the plum curculio, and remedies against same. 

1874.* Tracey, Wm. W., and Geo. Parmelee. — Injurious insects. Traverse City, 
Mich.; 12 pp. 

1874. Riley, C. V.— The Cultivator and Country Gentleman, vol. 39, p. 310. Copied 

from the Tribune.) 

Remarks on habits of the plum curculio and life-history notes. 



228 THE PLUM CURCULIO. 

1874.* Id. — The plum curculio; natural history; and how to catch him. N. Y. Semi- 
Weekly Tribune, May, 1874. 

Natural history of the plum curculio and remedies; figures several stages and 
machines in use. 

1875. Thomas, J. J. — Diseases and enemies of the plum.<4th Rept. Secy. St. Pom. 
Soc. Mich., 1874, pp. 35-36. 

Remedies against the plum curculio. 

1875. Lyon, T. T. — Plums and plum culture in Michigan. <4th Ann. Rept. Secy. 
St. Pom. Soc. Mich., 1874, pp. 237-238. 

Habits of the plum curculio and injuries. 

1875. Cook, A. J. — Insects injurious to the farm, garden, and orchard. <13th Ann. 
Rept. Sec. St. Bd. Agr. Mich., 1874, pp. 133-136, 2 figs., Separate, 1875, 
48 pp., 2 figs. 

1875. Bessey, C. E. — Report on insects injurious to plants and animals of the farm. 

<Rept. Iowa St. Agr. Soc, 1874, pp. 236-238, 1 fig. Separate: Des Moines, 
1875. 

1876. Fernald, Charles Henry. — Destructive insects, their habits, and means of 

preventing their depredations. <3rd Ann. Rept. Sec. Maine St. Pom. Soc, 
1875, pp. 23-24. 

Notes on life history of the plum curculio. 

1876.* Riley, C. V.— Plums and cotton.<N. Y. Weekly Tribune, May 17. 

Reply to inquiries regarding the plum curculio. Bands of cotton around trees. 

1877. Packard, Alphetjs Spring. — Report on the Rocky Mountain locust and other 

insects now injuring or likely to injure field and garden crops in the Western 
States and Territories. <Rept. IT. S. Geol. Surv., 1875, p. 795. 
Notes on the plum curculio. 

1877. Gott, B. — Report on some of our fruit insect enemies. < Ann. Rept. Ent. Soc 

Ont., 1877, p. 46, 1 fig. 

Observations on the plum curculio. 

1878. Saunders, W. — Annual address of the president of the Entomological Society 

of Ontario. <Can. Ent., vol. 10, p. 187, October; ib., p. 7. 
Notes on the plum curculio. 

1878. Perkins, G. H. — On some of the injurious insects of Vermont. <Bd. Agr., 1878, 

p. 268. 

1879. Gott, B— Notes of the year.<Ann. Rept. Ent. Soc. Ont., 1878, p. 56. 

Observations on the plum curculio. 

1879.* Riley, C. V.— Preventing rot in plums. <N. Y. Tribune, April 9. 

Propping and jarring recommended against the plum curculio. 

1880. Gott, B. — The plum curculio (Conotrachelus nenuphar). < Ann. Rept. Ent. 

Soc Ont., 1879, pp. 84-88, figs. 55-57. 

Habits of the plum curculio, injuries, parasites, and remedies. 

1881. Lintner, Joseph Albert. — Insects on plum trees. <Cultivator and Country 

Gentleman, vol. 46, p. 376, June 9. 

The plum curculio recorded attacking cherry. 

1883. Riley, C. V. — Recent advances in horticultural entomology. <Rural New 
Yorker, vol. 42, October 20. Reprint, p. 693. 
Discussion of remedies. 

1883. Weed, Clarence Moores. — Injurious insects new to Michigan. <15th 
Ann. Rept. Sec. St. Hort. Soc, 1882, p. 185. 
Scarcity of curculio noted. 

1883. Devereaux, W. L. — Coal tar for the plum weevil. <Can. Ent., vol. 15, p. 236, 

December. 

Inefflcacy of same. 



ECONOMIC BIBLIOGRAPHY. 229 

1883. Claypole, E. W. — Entomological notes for the summer of 1881.<Rept. Ent. 

Soc. Ont., 1882, p. 26. 

Injuries and remedies. 

1884. Weed, Clarence Moores. — The plum curculio again.<Trairie Farmer, 

October 4. 

Notes on jarring. 

1884. Riley, C. V.— Curculio, plum.<Supp. Encycl. Brit., 9th ed., vol. 2, p. 494. 
Natural history and remedies. 

1884. Saunders, W. — Annual address of the president of the Entomological Colonial 

Society of Ontario. <Can. Ent., vol. 16, p. 208, November. 

1885. Id.— Short notes.<15th Ann. Rept. Ent. Soc. Ont., 1885, pp. 17, 18. 

1885. Weed, Clarence Moores. — The plum curculio. <Prairie Farmer, vol. 57, p. 
345, May 30. 

Life history of the plum curculio; recommends jarring as a remedy. 

1885. Fletcher, James. — Report of the Entomologist. <Rept. Min. Agr. [Canada], 
p. 25, 1 fig. 

1885. Forbes, S. A. — Experiments on the codling moth and curculios (Carpocapsa 

pomonella Linn.; Anthonomus quadrigibbus Say; Conotrachelus nenuphar 
Herbst).<Trans. 111. St. Hort. Soc, 1885, n. s., vol. 19, pp. 103-119. Prairie 
Farmer, December 19, 1885. 

Details of experiments with arsenicals. 

1886. Webster, F. M. — Insects of the year.<Trans. Ind. Hort. Soc, 1885, p. 60. 

Characters of the plum curculio and injuries; remedies against same. 

1886. Saunders, W. — Annual address of the president of the entomological society 

of Ontario. <Can. Ent., vol. 18, p. 184, October. 17th Ann. Rept. Ent. Soc. 
Ont., 1887, p. 6. 

Brief note on the plum curculio. 

1887. Stickney, J. P.— Insect pests. <Trans. Wise. St. Hort. Soc, vol. 17, p. 235. 

Injuries produced by the plum curculio and remedies. 

1887. Lintner, Joseph Albert. —The curculio on the apple. ^Cultivator and 
Country Gentleman, vol. 52, p. 565, July 21. 

Probable injuries to apples by plum curculio; remedies against same. 

1887. Doran, E. W. — Report on the economic entomology of Tennessee. <Bien. 
Rept. Comm. Agr., etc., Tenn., pp. 221-224, 1 fig. 
History of the plum curculio and remedies. 

1887. Cook, A. J. — Notes on noxious insects. <26th Ann. Rept. Sec. St. Bd. Agr. 
Mich., 1886-1887, p. 451. 

Notes on the plum curculio. 

1887. Cook, A. J. — Experiments of Department of Zoology and Botany. <26th 
Ann. Rept. Sec St. Bd. Agr. Mich., 1886-1887, pp. 40-45. 
Remedies against the plum curculio. 

1887. Wier, D. B— Bui. 14, o. s., Div. Ent., IT. S. Dept. Agr., pp. 49-52. 

Extended discussion to show that native plums are practically curculio proof. 

1887. Weed, Clarence M. — Notes on Ohio Insects. <Ohio Farmer, Aug. 4, p. 66. 

Brief notes on the plum curculio. 

Id. — Recent developments in insect warfare.<Ohio Farmer, pp. 214, 230, 246, 
figs., October 6, 12, 20. 

Notes on the plum curculio. 

Id. — Some experiments in preventing the injuries of the plum curculio. < 
Proc 9th Ann. Meet. Soc Prom. Agr. Sci., pp. 90-95, 1 diagram. 

1888. Weed, Clarence M. — Report of the Entomologist. <7th Ann. Rept. Ohio 

Agr. Exp. Sta., pp. 146-150, 1 fig. 
Notes on the plum curculio. 



230 THE PLUM CURCULIO. 

1888. Cook, A. J.— Bui. 39, Mich. Agr. Coll. Exp. Sta., p. 8, September. 

Results of spraying with arsenicals for plum curculio, 

1888. Treat, Mary. — Curculio and injury to cherries. <Prairie Farmer, p. 538, 

August 18. 
1888. Harvey, F. L. — Report of the botanist and entomologist. < Ann. Rept. Maine 

Agr. Exp. Sta., pp. 178-181, 1 fig. 
Treats of plum curculio. 

1888. Fernald, C. H. — Injurious insects. <Trans. Mass. Hort. Soc, p. 112. 
Notes on the plum curculio. 

1888. McMillan, Conway. — Twenty-two common insects of Nebraska.^ Bui. Nebr. 
Sta., vol. 1, no. 2, pp. 45-50, fig. 1. 
Separate. 

1888. Comstock, John Henry.— Serious injury to apples by plum curculio. <Ins. 

Life, vol. 1, p. 193. 
1888. Brackett, G. C. — Rebuttal of Wier's statement regarding the plum curculio. 

<Ins. Life, vol. 1, p. 193. 
1888. Weed, Clarence M. — Seasonable insect notes. <Prairie Farmer, vol. 60, p. 

273, April 28. 

London purple as a remedy against the plum curculio. 

1888. Ashmead, Wm. Harris. — Entomological section. <Bul. 2, Fla. Agr. Exp. 
Sta., pp. 14-16. 

Notes on the plum curculio. 

1888. Lintner, J. A. — Proceedings New York Farmers, 1886-1887, 1 fig., pp. 53-54. 
Remedies against the plum curculio. 

1888. Bethune, Charles J. S. — Remedies for noxious insects. <18th Ann. Rept. 
Ent. Soc. Ont., 1 fig., pp. 53, 54. 

Characters of the plum curculio and habits. 

1888. Comstock, John Henry.— On the destruction of the plum curculio by poisons. 
<Bul. 3, Cornell Univ. Agr. Exp. Sta., pp. 40-43. 

The reason why poisons are effective against this insect as shown by experiment, 
and by quotations from Weed and Forbes. 

1888. Wier, B. D. — The curculio and the plum. < Farmer's Review, p. 644, Octo- 

ber 10. 

1889. Weed, Clarence M.— Recent developments in insect warfare. <Ann. Rept. 

Ohio St. Hort. Soc. f. 1888-1889, pp. 24, 25. 
Remedies against the plum curculio. 

1889. Marten, J. — Arsenical poisons for the plum and peach curculio. <Trairie 
Farmer, p. 516, 1 fig, August 10. 

1889. Weed, Clarence M. — Practical remedies for some Ohio insects; II. Insecti- 
cides and their application. <Bul. 8, Ohio Agr. Exp. Sta., pp. 4, 5; 1 fig. 
Id. — Remedies for the plum curculio. <Bul. Ohio Agr. Exp. Sta., 2d ser., vol. 

2, no. 6, pp. 133-143. 
Id. — Experiments with remedies for the plum curculio. <Ent. Amer., pp. 

204-207, October and November. 
Id. — Further experiments in preventing the injuries of the plum curculio. 
<Proc. 10th Ann. Meet. Soc. Prom. Agr. Sci., pp. 101-107. 
One diagram. 

1889. Webster, F. M. — Experiments in rearing the plum curculio from plums and 

other fruits.<Rept. Comm. Agr., 1888, pp. 78-79. 

Id.— Entomological experiments. <Bul. 25, Ind. Agr. Exp. Sta., pp. 5-9, 

Ifig. 

Experiments against the plum curculio. 



ECONOMIC BIBLIOGRAPHY. 231 

1889. Webster, F. M. -Entomology. <Ann. Kept. Ind. St. Bd. Agr., pp. 555-557. 

Notes on the plum curculio. 
1889. Neal, J. .— Entomologist's report.<Bul. 4, Fla. Agr. Exp. Sta., p. 14. 

Short notes on the plum curculio. 
1889. Riley, C. V.— The plum curculio, arsenical sprays, Wier's wild plum immu- 
nity theory. <Proc. 22d sess. Amer. Pom. Soc, pp. 13-36. 
1889. Smith, J. B.— Report of the entomologist. <10th Ann. Rept. N. J. Agr. Exp. 

Sta., pp. 296-298. 

Brief account of the plum curculio. 
1889. Cook, A. J.— Remedies for curculio. <Rural New Yorker, p. 677, October. 
1889. Gillette, C. P.— Important injurious insects. <Bul. 5, Iowa Agr. Exp. Sta. 

p. 181. 

Notes on the plum curculio. 

1889. Btjdd, J. L — Curculio-proof plums. <Orchard and Garden, p. 137, July. 
1889. Beckwith, M. H.— Injurious insects.<Bul. 4, Del. Agr. Exp. Sta., pp. 10-12, 
1 fig.; 2d Ann. Rept. Del. Agr. Exp. Sta., pp. 120-122, 1 fig. 
Brief account of the plum curcu)' ; 
1889. Wier, B. D— The plum curculio. <Fruit Grower's Journal, November 1. 
1889. Bruner, Lawrence.— Report of the entomologist. < Ann. Rept. Nebr. St. 
Bd. Agr., 1888, pp. 124-127, 1 fig. 
Treats of plum curculio. 

1889. Riley, C. V., and Howard, L. 0.— The plum curculio. <Rept. Ent. in Rept. 

Corn'm. Agr. for 1888, pp. 57-79. 

Detailed account of the plum curculio, with remedies. 

1890. Weed, C. M.— I. Plum curculio experiment. <Bul. Ohio Agr. Exp. Sta., 

2d ser., vol. 3, no. 8, pp. 225-228. 
Id.— A third season's experiments with remedies for the plum curculio. 

<Proc. 11th Ann. Meet. Soc. Prom. Agr. Sci., 1890, pp. 44-46. 

Id.— A season's work among the enemies of the horticulturist. <Proc. Ohio 

St. Hort. Soc, p. 12. 

Notes on the plum curculio. 

1890. Smith, J. B— Notes on the plum curculio. <Garden and Forest, 1890, p. 560. 
1890. Webster, F. II — Experiments with the plum curculio. <Ins. Life, vol. 2, 
pp. 305-310, April. 
Id.— Entomological notes.<Bul. 33, Ind. Agr. Exp. Sta., pp. 36^1, 1 fig. 
1890 Riley, C. V., and Howard, L. O.— The puncturing of apples by the plum 
curc'ulio.<Ins. Life, vol. 2, pp. 383-384, 1 fig., May and June. 
Short note on injury to apples by the plum curculio. 

1890. Reynolds, H.— The plum curculio. <Massaehusetts Ploughman, August 9. 
1890. Beckwith, M. H— Our injurious insects. <Trans. Penin. Hort. Soc, pp. 

87, 88. 
1890. Green, S. B.— London purple for the curculio on native plums.<Bul. 10, 

Minn. Agr. Exp. Sta., pp. 71, 72. 

Remedies against the plum curculio. 

1890. Webster, F. M.— Entomological notes.<Bul. 33, Ind. Agr. Exp. Sta., pp. 

36-39. 

Experiments against plum curculio. 

1890. Hopkins, A. D.— Report of the entomologist. <3d Ann. Rept. W. Va. Agr. 

Exp. Sta., pp. 151, 152. 

Remedies against the plum curculio. 



232 THE PLUM CURCULIO. 

1890. Chittenden, F. H. — Notes on the habits of some species of Rhynchophora. 
<Ent. Amer., p. 170, September. 

Biological notes on the plum curculio. 

1890. Lelong, B. M. — Injurious insects. <Rept. Cal. St. Bd. Hort., 1889, pp. 
223-228, 2 figs. 

Treats of plum curculio. 

1890. Cook, A. J.— The plum curculio. <Bul. 66, Mich. Agr. Exp. Sta., p. 8, 1 fig. 
Various remedial measures against the plum curculio. 

1890. Cook, A. J. — Latest methods with curculio. <Proc. Mich. Hort. Soc, 1889, 

pp. 37-39, 1 fig. 
1890. Gillette, C. P. — The plum curculio and the plum gouger.<Bul. 9, Iowa 
Agr. Exp. Sta., pp. 371-378. 

Life history notes and parasites of the plum curculio, with remedies. Relative 
injury to varieties of plums. 

1890. Murtpeldt, M. E. — Entomological notes from Missouri for the season of 1899. 
<Bul. 22, Div. Ent., U. S. Dept. Agr., p. 74. 

1890. Osborn, Herbert. — Entomology. <Orange Judd Farmer, p. 372, June 14. 
Experiments relative to plum curculio. 

1890. Osborn, Herbert. — Entomology. <Orange Judd Farmer, p. 277, May 3. 

Notes on the plum onrculio. 

1891. Weed, H. E. — Injurious insects. <Miss. Agr. Exp. Sta., Bui. 14, pp. 22-26, 

Ifig; 

General account of the plum curculio. 

1891. Weed, C. M. — A review of some plum curculio literature. < Amer. Nat., 
pp. 63-72, January. 
Id. — Insect talks — 17.<Natl. Stockman and Farmer, p. 587, figs., October 8. 
Id. — Insect injuriously affecting fruits, shade trees, and flowers. <Ann. 
Rept. Columbus Hort. Soc, 1890, pp. 60-62, 1 fig. 
Brief account of the plum curculio. 

1891. Smith, J. B. — Notes on the plum curculio. <Ins. Life, vol. 3, pp. 219, 220, 
January. 
Id.— Report of the Entomologist. <12th Ann. Rept. N. J. Agr. Exp. Sta., 

pp. 420-423, 1 fig. 

Reprint of Buls. 82 and 85 and Spec. Bui. N, with brief additions. 

1891. Fernald, C. H. — Division Entomology. <Bul. 12, Mass. Agr. Exp. Sta., 

p. 16, lfig. 

Brief note on the plum curculio. 

1891. Forbes, S. A. — Transactions Department of Agriculture of Illinois. <17th 
Rept. 111. St. Ent. Separate: Springfield, 111., pp. 21-25. 
Experiments with arsenites against the plum curculio. 

1891. Hopkins, A. D. — (1) Farm and garden insects. (2) Notes of the season. 
<Bul. 14, W. Va. Agr. Exp. Sta., pp. 71, 72. 
Brief notes on the plum curculio. 

1891. Gillette, C. P. — Notes on the plum curculio and plum gouger.<Ins. Life, 

vol. 3, pp. 227-229. 

Egg-laying record of the plum curculio and remedies. 

1891. Lintner, J. A. — 7th Rept. on injurious and other insects of the State of New 
York.<44th Rept. N. Y. Mus. Nat. Hist., pp. 288-296, 4 figs. 
Review of the year, with notes on plum curculio. 

1891. McCarthy, G— Some injurious insects. <Bul. 78, N. Car. Agr. Exp. Sta., 
p. 261, 1 fig. 

Brief compiled notes on the plum curculio. 



ECONOMIC BIBLIOGRAPHY. 233 

1891. Murtfeldt, M. E. — Entomological notes for the season of 1890. <Bul. 23, 
Div. Ent., U. S. Dept. Agr., p. 47. 

Short notes on the plum curculio. 

1891. Osborn, H. — Entomology. <Orange Judd Farmer, p. 356, June 6. 
1891. Osborn, H. — Entomology. <Orange Judd Farmer, p. 36, July 18. 
1891. Fletcher, J. — Recommendations for the prevention of damage by some 

common insects of the farm, the orchard, and the garden. <Bul. 11, Can. 

Exp. Farms, p. 23. 

Remedies against the plum curculio. 

1891. Weed, C. M. — Miscellaneous experiments in the control of injurious insects. 
<Ohio. Agr. Exp. Sta. Bui., vol. 4, no. 2, p. 42. 

Deals with spraying as remedy against plum curculio. 

1891. Murtfeldt, M. E. — Entomological notes for the season. Reports of observa- 

tions and experiments in the practical work of the Division of Entomology. 
<Bul. 26, Div. Ent., U. S. Dept. Agr., p. 37. 
Brief note on the plum curculio. 

1892. Smith, J. B. — Spraying for insect and iungous pests of the orchard and vine- 

yard. <Bul. 86, N. J. Agr. Exp. Sta., p. 5. 
Treatment for plum curculio. 

1892. Kinney, L. F. — Fungicides and insecticides. <Bul. 15, R. I. Agr. Exp. Sta., 
p. 25. 

Treatment for plum curculio. 

1892, Cook, A. J.— Entomological reports.<Rept. Mich. Agr. Exp. Sta., f -1891-92, 
pp. 123-127. 

Use of arsenicals against plum curculio. 

1892. Smith, J. B. — Spraying for insect pests of the orchard. <Bul. 86, N. J. Agr. 
Exp. Sta., p. 5. 

Remedies against plum curculio. 

1892. Riley, C. V. — Remedies for the plum curculio. < American Farmer, p. 24, 

March 1. 

Traps and spraying against plum curculio. 

1892. Marten, J. — Description of the 25 horticultural insects referred to in this 
article on page 121.<Trans. 111. St. Hort. Soc, pp. 219-222, 1 fig. 

Describes insects earlier mentioned by Forbes, including the plum curculio. 

1892. Stinson, J. T. — Some insects and fungous diseases and their remedies. 
<Bul. 21, Ark. Agr. Exp. Sta., pp. 59, 60. 
Spraying against the plum curculio. 

1892. Fletcher, James. —Injurious insects. <Farmer's Advocate, London, Ontario, 
p. 199, 1 fig. 

Economic notes on plum curculio. 

1892. Garman, H. — Some common pests of the farm and garden.<Bul. 40, pp. 34, 

35, Kent. Agr. Exp. Sta., and 5th Ann. Rept., pp. 74, 75. 
Treats of plum curculio. 

1893. Weed, C. M. — A second season's work among the enemies of the horti- 

culturist. <Proc. Ohio St. Hort. Soc, pp. 3-11, fig. 

1893. Alwood, W. B. — Injurious insects and diseases of plants, with remedial 
measures for the same.<Bul. 24, Va. Agr. Exp. Sta., p. 8. 

1893. Murtfeldt, M. E.— Report on Insects of Missouri for 1892. Report of observa- 
tions and experiments in the practical work of the Division of Entomology. 
<Bul. 30, Div. Ent., U. S. Dept. Agr., p. 56. 
Scarcity of parasites of the plum curculio. 



234 THE PLUM CUKCULIO. 

1893. Weed, C. M. — The treatment of neglected apple orchards. <Rept. N. H. 
Agr. Exp. Sta., f. 1893, p. 175. 

Brief account of the plum curculio. 

1893. Goff, E. S. — The plum curculio in Door County, Wisconsin. <Ins. Life, 

vol. 6, pp. 36-38. 

Notes on plum curculio. 

1894. Webster, F. M. — Plum curculio insect in dewberry. <Ohio Farmer, p. 117, 

February 8. 

1894. Sturgis, W. C. — Some injurious insects. <18th Ann. Rept. Conn. Agr. Exp. 
Sta., pp/141-142. 

Brief notes on plum curculio. 

1894. Stinson, J. T. — Insects injurious to fruits and vegetables, and remedies for 
destroying them.<Bul. 33, Ark. Agr. Exp. Sta., pp. 74-77, 1 fig. 

1894. Price, R. H. — Injurious fungi and insects. <Bul. 32, Tex. Agr. Exp. Sta., 
pp. 493, 494, 1 fig. 

Remedies against plum curculio. 

1894. Lugger, Otto. — A few enemies of the plum.<\A.nn. Rept. Minn. St. Hort. 
Soc, pp. 417-418, 1 fig. 

Notes on plum curculio. 

1894. Bruner, Lawrence.— Insect enemies of the apple tree and its fruit.<Ann. 
Rept. Nebr. St. Hort. Soc, p. 161. 
Plum curculio listed. 

1894. Jack, A. G. — The plum curculio as an apple pest.<Garden and Forest, 
pp. 44-45. 

Id. — Notes on some injurious insects. <Trans. Mass. Hort. Soc, p. 140. 
Notes on plum curculio. 

1894. Hatch, A. L. — Enemies of orchard fruits. <Trans. 111. St. Hort. Soc, 

pp. 323-325. 

Treats of plum curculio. 

1895. Smith, J. B. — The plum curculio on apple. <Garden and Forest, p. 104. 
1895. Slingerland, M. V. — The plum curculio on apples. <Rural New Yorker, 

p. 457, July 6. 
1895. Fletcher, James. — Report of the entomologist and botanist. <Rept. Exp. 
Farms, Canada, 1894, p. 156, 1 fig. 

Economic notes on plum curculio. 

1895. Marion, J. H. — The plum curculio. <Colman's Rural World, p. 203, June 27. 

Experience with jarring for plum curculio. 

1895. Murtfeldt, M. E. — Habits of the plum curculio. <Golman's Rural World, 
p. 35, January 31. 

1895. Fletcher, J. — Injurious insects. <Bul. 23, Exp. Farms, Canada, p. 21, 1 fie\ 

Remedies against plum curculio. 

1895. Schwarz, E. A. — Some notes on Melsheimer's Catalogue of the Coleoptera of 
Pennsylvania. <Proc Ent. Soc. Wash., vol. 3, p. 137. 

Comments on Melsheimer's error in believing curculio oviposited in peach twigs. 

1895. Riley, C. V. — (Comments on above paper by Mr. Schwarz — ) Proc Ent. Soc. 
Wash., vol. 3, p. 138. 

States that Melsheimer's statement might to a certain extent be correct. Records 
finding oviposition marks on pear twigs. 

1895. McCarthy, G. — The peach tree and its parasites. <Bul. 120, N. C. Agr. 
Exp. Sta., p. 293, 1 fig., November. 
Mentions plum curculio. 



ECONOMIC BIBLIOGEAPHY. 235 

1896. Slingerland, M. V. — Spotted plums. <Rural New Yorker, p. 672, October 
10. 

Work of plum curculio. 

1896. Slingerland, M. V. — Report as chairman of committee on entomology. 
<Proc. West. N. Y. Hort. Soc., 1896, pp. 18-19. 
Notes on plum curculio. 

1896. Goff, E. S. — Miscellaneous horticultural work.<Wisc. Agr. Exp. Sta. Rept. 
f. 1895, p. 303. 

Notes on plum curculio. 

1896. Price, R. H.— The peach.<Bul. 39, Tex. Agr. Exp. Sta., pp. 844-845, 1 fig. 

Brief notice, injuries to peach, remedial measures with reference to plum cur- 
culio. . 

1896. Lugger, Otto. — Insects injurious in 1896. <Bul. 48, Minn. Agr. Exp. Sta., 

1896, pp. 69-71, 1 fig., December. 

1897. Webster, F. M., and Mally, C. W. — Insects of the year in Ohio.<Bul. 9, n. s., 

Div. Ent., U. S. Dept. Agr., p. 43. 
Brief notes on plum curculio. 

1897. Slingerland, M. V. — Life history of the plum curculio. <Rural New 
Yorker, p. 354, 1 fig., May 29. 
Id. — Plum curculio and its eggs.<76., p. 420, June 26. 
1897. Johnson, W. G. — Destructive insects and methods of controlling them. 
<American Gardening, no. 1, p. 22, January 2. 
Id.— March 13, p. 174, 1 fig. 

1897. Bogue, E. E. — Some injurious orchard insects. <Bul. 26, Okla. Agr. Exp. 
Sta., p. 18, 1 fig. 

Brief note on the plum curculio. 

1897. Butz, George C. — The peach industry in Pennsylvania. Curculio (Cono- 
trachelus nenuphar). <Bul. 37, Pa. Agr. Exp. Sta., p. 27. 
Brief notes on the plum curculio; recommends jarring. 

1897. Fletcher, James. — Report of the entomologist and botanist. <Rept. Exp. 
Farms, Canada, 1896, p. 255. 

Brief note on the plum curculio. 

1897. Johnson, Willis G. — Notes from Maryland on the principal injurious insects 
of the year.<Bul. 9, n. s., Div. Ent., U. S. Dept. Agr., p. 82. 

Records great injury to peaches; also attack of apples, pears, and plums. 

1897. Panton, J. H. — Instructions in spraying. <Bul. 105, Out. Agr. College and 
Exp. Farms, p. 10. 

Remedies against plum curculio. 

1897?. Kinney, L. F. — The plum rot and its effect on plum culture in Rhode Island. 
<Rept. R. I. Agr. Exp. Sta., p. 191, 1896. 

1897?. Earle, F. S— Japanese plums. <Bul. 85, Ala. Agr. Exp. Sta., pp. 423-448. 

Remedies against plum curculio. 
1897?. Goff, E. S. — Miscellaneous Horticultural Work.<Wisc. Agr. Exp. Sta., 
Rept., 1896, pp. 234-235. 

Remedies against plum curculio. 

1897. Lelong, B. M. — Insect pests and tree diseases liable to be introduced into the 

State and especially to be guarded against. <5th Bien. Rept. Cal. St. Bd. 
Hort., 1895-1896, p. 25. 

1898. Smith, J. B. — Report of the entomological department of the New Jersey 

Agricultural College Experiment Station for 1897. <Ann. Rept. N. J. Agr. 
Exp. Sta., 1897, pp. 404-405. 

Brief note on plum curculio. 



236 THE PLUM CURCULIO. 

1898. Gillette, C. P. — Colorado's worst insect pests and their remedies. <Bul. 
47, Colo. Agr. Exp. Sta., p. 22. 

Brief account of the plum curculio. 
1898. Johnson, W*. G. — Report on the San Jose scale in Maryland, and remedies for 
its suppression and control. <Bul. 57, Md. Agr. Exp. Sta., p. 6. 
Brief notes on plum curculio. 
1898. Slingerland, M. V.. — How the curculio mounts the plum trees. <Rural 

New Yorker, p. 656, September 24. 
1898. Faville, E. E., and Parrott, P. J. — Some insects injurious to the orchard. 
<Bul. 77, Kans. Agr. Exp. Sta., pp. 41-43, fig. 1. 
Notes on the plum curculio. 

1898. Fernald, H. T. — Insects to be treated now by fruit growers. The apple worm 

and plum curculio. <Farmer's Cir. 2, Pa. Dept. Agr., May. 
Brief account of the plum curculio. 
1099. Slingerland, M. V. — How insects spend the winter.<Rural New Yorker, 
p. 55, January 28; p. 116, February 18. 

1899. Webster, F. M.— Inquiries answered. <Ohio Farmer, p. 382, November 16. 

Transformation of the plum curculio. 
1899. Tillinghast, J. A., and Adams, G. E. — Suggestions as to spraying.<Bul. 
52, R. I. Agr. Exp. Sta., pp. 35-36. 

Brief account of the plum curculio. 
1899. Starnes, Hugh N— Some peach notes.<Bul. 42, Ga. Agr. Exp. Sta., pp. 
227-228, 1 fig. 

Brief account of the plum curculio. 
1899. Harvey, F. L., and Munson, W. M. — Apple insects of Maine. <Bul. 56, 
Maine Agr. Exp. Sta., pp. 134-136. 

General account of the plum curculio, with description of stages. 
1899. Lugger, Otto. — Beetles injurious to fruit-producing plants. <Bul. 66, 
Minn. Agr. Exp. Sta., pp. 285-290, 6 figs. 
Popular account of the plum curculio. 
1899. Johnson, W. G.— Miscellaneous entomological notes. <Bul. 20, n. s., Div 
Ent., U. S. Dept. Agr., p. 64. 

Mention of the plum curculio. 
1899. Beach, S. A., Lowe, V. H., and Stewart, F. C. — Common diseases and 
insects injurious to fruits. <Bul. 170, N. Y. St. Agr. Exp. Sta., pp. 433^34. 
Brief account of the plum curculio. 
1899. Fletcher, James. — Report of the entomologist and botanist. <Rept. Exp. 
Farms Can., 1898, pp. 202-203. 

Destruction of apples and plums by the plum curculio. 
1899. Bruner, Lawrence. — Insect enemies of the apple and its fruit.<Ann. 
Rept. Nebr. St. Hort. Soc, 1898, p. 208, 1 fig. 
Note on the plum curculio . 
1899. Fernald, H. T. — Some insects attacking fruit and fruit trees. <Bul. 47, Pa. 

Dept. Agr., pp. 18-19. 

Brief account of life history, injuries, and treatment of the plum curculio. 

1899. Doane, R. W. — Insects and diseases affecting the prune. <Bul. 38, Wash. 

Agr. Exp. Sta., pp. 43-44. 

Brief description of the plum curculio and remedies against same. 

1900. Close, C. P.— Plant diseases and insect pests.<Bul. 65, Utah Agr. Exp. 

Sta., pp. 87-88. 

Remedies against plum curculio. 
1900. Cooley, R. A.— Injurious fruit insects. <Bul. 23, Mont. Agr. Exp. Sta., pp. 

78, 79, 1 fig. 

Brief account of the plum curculio; injuries, life history, and remedies. 

1900. Johnson, W. G. — Notes on insects of economic importance for 1900.<Bul. 
26, n. s., Div. Ent., U. S. Dept. Agr., p. 83. 
Brief note on the plum curculio. 



ECONOMIC BIBLIOGRAPHY. 237 

1900. Sanderson, E. D— Notes from Delaware. <Bul. 26, n. a., Div. Ent., U. S. 
Dept. Agr., p. 67. 

Brief note on the plum curculio. 
1900. Smith, J. B.— The plum curculio.<Ent. Cir. 17, N. J. St. Bd. Agr., pp. 2. 
Remedies against the plum curculio. 

1900. Weed, C. M.— Insect record for 1899.<Bul. 72, N. H. Agr. Exp. Sta., pp. 68-69. 

Notes on the plum curculio. 

1901. Bruner, L., and Hunter, W. D. — Insect enemies of the stone fruits. <Ann. 

Rept. Nebr. St. Hort. Soc, 1900, pp. 111-113, 1 fig. 

Life history of the plum curculio and remedies against same. 
1901. Felt, E. P.— Plum curculio. <Country Gentleman, p. 604, July 25. 

Injury to leaves of plum by plum curculio. 
1901. Felt, E. P. — 16th Rept. on the injurious and other insects of the State of New 
York.<Bul. N. Y. St. Mus., vol. 7, no. 36, p. 989, 1900. 
Brief account of the plum curculio. 

1901. Fletcher, James. — Report of the Entomologist and Botanist. <Ann. Rept. 
Exp. Farms, Can., 1900, p. 239. 

Injury to apples by the plum curculio. 
Brief note on the plum curculio- 

1901. Green, E. C. — Insect enemies of tree and fruit and how to control them. 
<Trans. 111. Hort. Soc, 1900, pp. 114-125, p. 122. 
Remedies against the plum curculio. 

1901. Quaintance, A. L. — Insect notes. <13th Ann. Rept. Ga. Agr. Exp. Sta., 
1900, p. 365. 

Brief note on the plum curculio. 

1901. Slingerland, M. V. — Do curculios crawl or fly?<Rural New Yorker, p. 104, 

February 16. 
1901. Slingerland, M. V. — Fighting the plum curculio. <Rural New Yorker, p. 

288, April 20. 

Coal tar does not give sufficient results. 

1901. Smith, W. B. — Insect enemies to fruit and their remedies. <Proc Columbus 
Hort. Soc, p. 61. 

Remedies against the plum curculio. 

1901. Snyder, A. H. — Insects injurious to fruit. <Proc Columbus Hort. Soc, p. 56. 
Brief note on the plum curculio. 

1901. Fletcher, J. — 31st Ann. Rept. Ent. Soc. Ontario. <Rept. Ont. Ent. Soc, 
1900, p. 71. 

Brief note on the plum curculio. 

1901. Sherman, F., Jr. — Injurious insects. <Bul. 6, N. C. St. Bd. Agr., vol. 22, pp. 

27-28, 1 fig. 

1902. Banks, N. — Principal insects liable to be distributed on nursery stock. <Bul. 

34, n. s., Div. Ent., U. S. Dept. Agr., pp. 45-46. 
Biological notes on the plum curculio. 

1902. Cranefield, F. — Plum insects and diseases. <Wisc Agr., p. 10, January 9. 
Recommends jarring against the plum curculio. 

1902. Fiske, W. F. — Notes on certain injurious insects in Georgia. <Proc Ga. St. 
Hort. Soc, 1902, p. 77. 

Discusses remedies for use against the plum curculio. 

1902. Gillette, C P. — Insects and insecticides. <Bul. 71, Colo. Agr. Exp. Sta., 

p. 14. 

Brief description of the plum curculio. 

1902. Goff, E. S. — Coal tar for plum curculio. < Wise Agr., p. 11, May 15. 

Advises against coal tar as remedy for plum curculio. 



238 THE PLUM CUKCULIO. 

1902. Gossard, H. A. — Report of committee on entomology.<Trans. Fla. Hort. 

Soc, p. 101. 

Brief note on the plum curculio. 

1902. Howard, L. 0. — Notes from correspondence. <Bul. 38, n. s., Div. Ent., U. S. 
Dept. Agr., p. 109. 

Treats of parasites of the plum curculio. 

1902. Johnson, W. G. — Insect warfare in peach orchards. <American Agriculturist, 
p. 588, April 26. 

Jarring for plum curculio. 

1902. Munson, W. M. — Habits of the plum curculio. < Rural New Yorker, p. 302, 

April 26. 
1902. Murtfeldt, M. E. — Drought, heat, and insect life.<Bul. 31, n. s., Div. Ent., 

U. S. Dept. Agr., pp. 97, 98. 

Note on effect of drought on the plum curculio. 

1902. Murtfeldt, M. E. — Recent experiments with destructive insects. <Rept. Mo. 
State Hort. Soc, p. 254. 

Plum curculio not much reduced in numbers by unusual climatic conditions. 

1902. Scott, W. M., and Fiske, W. F. — Jarring for the curculio on a large scale in 
Georgia, with a list of the insects caught. <Bul. 31, n. s., Div. Ent., TJ. S. 
Dept. Agr., pp. 24-27, 2 pis. 

Account of jarring for plum curculio on a large scale. 

1902. Slingerland, M. V. — What the plum curculio does.<Rural New Yorker, p. 

400, June 7. 

Habits of the plum curculio. 

1902. Smith, J. B. — The entomologist's experiment orchard. <Bul. 155, N. J. Agr. 
Exp. Sta., pp. 54, 56. 

Life history of the plum curculio and remedies against same. 

1902. Stedman, J. M. — Some orchard pests.<34th Ann. Rept. Mo. St. Bd. Agr., 

p. 220. 

Brief note on the plum curculio. 

1902. Fernald, H. T. — Some common pests of the farmer. <Bul. 99, Pa. Dept. Agr., 

pp. 23, 24. 

Life history of the plum curculio and remedies against same. 

1902. Smith, J. B— Report of the Entomologist. <N. J. Agr. Exp. Sta. Rept., 1901, 

p. 484. 

Brief account of the plum curculio. 

1902. Quaintance, A. L., and Smith, R. I. — Egg-laying record of the plum curculio. 
<Bul. 37, n. s., Div. Ent., IT. S. Dept. Agr., pp. 105-107. 

Table showing egg deposition of 9 female curculios during their lives. 

1902. Edwards, C. H. — Second biennial report of the Montana State Board of 

Horticulture. <Mont. St. Bd. Hort., Rept., 1901-2, p. 80. 
Brief note on the plum curculio. 

1903. Titus, E. S. G. — Insects other than the codling moth injurious to the fruit of 

the apple. <Trans. 111. St. Hort. Soc. for 1902, pp. 138-162. 
Life history of the plum curculio and habits of same. 

1903. Washburn, F. L — Injurious insects of 1903. <Bul. 84, Minn. Agr. Exp. Sta., 
p. 88, 1 fig. Also 8th Rept. St. Ent. Minn., p. 88, 1 fig. 
Notes on the plum curculio. 

1903. Chittenden, F. H. — The principal injurious insects in 1902. <Ybk. Dept. 
Agr., 1902, p. 731. 

Mention of plum curculio. 

1903. Felt, E. P. — 19th Report of the State Entomologist on injurious and other 
insects of the State of New York.<Bul. 76, N. Y. St. Mus., p. 137. 
Brief notes on the plum curculio. 



ECONOMIC BIBLIOGRAPHY. 239 

1903. Surface, H. A. — Monthly Bulletin, Division Zoology, vol. 1, no. 2, Pa. 
Dept. Agr., June, p. 11. 

Brief note on the plum cureulio. 

1903. Sherman, F., Jr. — Injurious insects. Spraying for insects and diseases. 
<Bul. 24, N. C. St. Bd. Agr., 1903, no. 6, pp. 28-29, 1 fig. 

Short descriptive, biological, and economic notes on the plum cureulio. 

1903. Osborn, H. — The insect problem. <Columbus Hort. Soc, vol. 18, no. 2, 
pp. 41, 42. 

Statistics showing extent of damage by the plum cureulio. 

1903. Sanderson, E. D. — Report of the entomologist. <Del. St. Rept. 1902, pp. 

109-151. 

Arsenicals found to be effective in control of plum cureulio on cherry but not on 
apple. 
1903. Horsfall, F — Orchard enemies. <Bul. 9, Mo. Fruit Station, pp. 27, 28. 
Notes on habits, life history, and means of combating the plum cureulio. 

1903. Sherman, F., Jr. — Insect enemies of apple, pear, and quince, with methods 
of treatment. <Bul. 183, N. C. Agr. Exp. Sta., p. 59, 1 fig. 
Brief economic and biological notes on the plum cureulio. 

1903. Sherman, F., Jr. — Insect and fungus enemies of the peach, plum, cherry, 
fig, and persimmon. <Bul. 186, N. C. Agr. Exp. Sta., pp. 7-8. 
Brief notes on the plum cureulio. 

1903. Horsfall, F. — Orchard enemies. <Bul. 9, Mo. Fruit Station, p. 27. 

Remedies against the plum cureulio. 

1904. Lochhead, W. — Insects of the season. <34th Ann. Rept. Ent. Soc. Ont., 

1903, p. 33. 

Note on occurrence of the plum cureulio. 

1904. Pettit, R. H. — Insects injurious to fruits in Michigan. <Spec. Bui. 24, Mich. 
Agr. Exp. Sta., pp. 65, 66. 

Brief account of life history of the plum cureulio and remedies against same. 

1904. Slingerland, M. V. — Some serious insect depredations in New York in 1903. 
<Bul. 46, Div. Ent., IT. S. Dept. Agr., p. 72. 
Remedies against the plum cureulio. 

1904. Slingerland, M. V. — Save the quinces and plums. < American Agriculturist, 
p. 551, May 14. 

Remedies against the plum cureulio. 

1904. Weed, C. M.— The insect record for 1903. <Bul. 115, N. H.Agr. Exp. Sta., 
p. 174; Ann. Rept., 1904, p. 259. 

Brief notes on the plum cureulio. 

1904. Forbes, S. A. — Spraying apples against the plum cureulio. <Bul. 52, Bur. 
Ent., U. S. Dept. Agr., p. 49. Papers read before Ass. Econ. Ent., Dec. 30, 

1904. Published as Bulletin 108, 111. Agr. Exp. Sta. (May, 1906). 

1904. Farrand, T. A. — Report of the South Haven Substation for 1903.<Spec. 
Bui. 27, Mich., pp. 3-4. 

Dust v . liquid sprays against the plum cureulio. 

1904. Chittenden, F. H. — The principal injurious insects of 1903. <Ybk. Dept. 
Agr. f. 1903, p. 565. 

Remedies against the plum cureulio. 

1904. Cooley, R. A. — 1st Annual Report of the State Entomologist of Montana. 
<Bul. 51, Mont. Agr. Exp. Sta., p. 256. 
Remedies against the plum cureulio. 

1904. Fletcher, J. — Insects of the year in Canada. <Bul. 46, Bur. Ent., U. S. 
Dept. Agr., p. 82. 

Mention of the plum cureulio. 



240 THE PLUM CURCULIO. 

1904. Surface, H. A. — Monthly Bulletin, Division of Zoology, vol. 2, no, 2, 
Pa. Dept. Agr., p. 63, June. 

Remedies against the plum curculio. 

1904. Washburn, F. L. — 9th Annual Report of the State Entomologist of Minn., 
pp. 109-115, 3 figs. 

Plum curculio as enemy to apples; discusses injuries, habits, and remedies. 

1904. Sanderson, E. Dwight. — The plum curculio. <Cir. 6, Ent. Dept. Texas Agr. 
Exp. Sta., pp. 1-3, 3 figs. 

Brief summarized account of the plum curculio. 

1904. Fulton, J. A.— Peach culture, p. 133. 

Discusses plum curculio, giving numerous proposed remedies. 
1904. Cooley, R. A. — 2d Annual Report of the State Entomologist. <Bul. 55, Mont. 
Agr. Exp. Sta., pp. 171-172. 

Brief account of the plum curculio. 

1904. Stedman, J. M. — The sting in the apple. The work of the plum curculio in 
the apple. <Bul. 64, Mo. Stat., pp. 24, 10 figs. 

Discusses the life history and habits of the plum curculio in apple orchards; 
remedies. 

1904. Chittenden, F. H.— The cherry fruit fly.<Bul. 44, Div. Ent., U. S. Dept. 
Agr., p. 72, figs. 18. 

Introduces new figures, showing larva, pupa, and adult of plum curculio. 

1904. Washburn, F. L.— Injurious insects of 1904.<Rept. St. Ent. Minn., 1904, 

pp. 109-115, 3 figs. 

Discussion of injury to apples by plum curculio. 

1905. Crandall, C. S. — The curculio and the apple. <Bul. 98, 111. Agr. Exp. Sta. 

An extended account of the plum and apple curculios, giving results of thorough 
life-history studies and experiments with arsenical sprays during 1903 and 1904. 

1905. Britton, W. E. — Fourth Report of the State Entomologist. <Conn. Storrs 
Stat. Rept., 1904, pt. 3, pp. 219-221, 1 fig. 
Injury to apples by curculio. 

1905. Burgess, A. F. — Report of the chief inspector of nurseries and orchards. 
<Ohio Dept. Agr., Div. Nurs. and Orch. Insp., Rept., 1905, pp. 10-11. 

1905. Quaintance, A. L. — The principal insect enemies of the peach. <Ybk. TJ. S. 

Dept. Agr., pp. 325-330, 1905. 

General account of curculio, with recommendations for use of arsenicals; jarring 
and cultivations. 

1906. Johnson, F., and Girault, A. A. — The plum curculio. <Cir. 73, Bur. Ent., 

U. S. Dept. Agr., pp. 10, 5 figs. 

Life history and habits of plum curculio; remedies. 

1906. Slingerland, M. V. — Cooperative spraying experiments. <Bul. 235, Cornell 
Agr. Exp. Sta., pp. 160-165. 

Report on results of arsenate of lead against plum curculio by New York 
orchardists. 

1906. Quinn, G. — Seasonable notes on some orchard pests. <Journ. Dept. Agr. So. 

Austr., vol. 10, no. 1, pp. 9-14. 

Remedies against plum curculio. 

1907. Adams, C. F. — Some insects of orchard and other fruits.<Bul. 92, Ark. Agr. 

Exp. Sta., pp. 11-12, 1 fig. 

Brief biological and economic notes on plum curculio. 

1907. Smith, J. B— Report of the Entomologist. <N. J. Sta. Rept. f. 1906, p. 520. 
1907. Houghton, C. O. — Report of the Entomologist. <Del. Coll. Agr. Exp. Sta. 
Repts., 1905-1906, pp. 83-85. 

Remedies. Little benefit was noted from the use of sticky bands in capturing 
plum curculio. 



1908. 



1908. 



ECONOMIC BIBLIOGRAPHY. 241 

1908. Morris, 0. M., and Nicholson, J. F — Orchard spraying. <Bul. 76, Okla. 
Agr. Exp. Sta., pp. 23-24, 1 fig. 

Brief account of the plum curculio. 
Patch, Edith M — Insect notes for 1908. <Bul. 162, Maine Agr. Exp. Sta., 
p. 363. 

Brief account of the plum curculio. 
Washburn, F. L. — The apple leafhopper and other injurious insects of 1907 
and 1908.<Bul. 112, Minn. Agr. Exp. Sta., pp. 227-234, 4 figs. 

Results of spraying plum trees with arsenate of lead against plum curculio: life 
history notes. 

1908. Smith, J. B. — Insecticide materials and their application, with suggestions for 
practice. <BuL 213, N. J. Agr. Exp. Sta., pp. 45-46. 
Remedies against plum curculio. 

1908. Taylor, E. P. — Report of the department of entomology. <Mo. State Fruit 
Exp. Sta., Rept., 1907-8, pp. 13-14. 

Results of experimental spraying against plum curculio. 

1908. Worsham, E. L— Report of the past year's work of the State board of ento- 

mology. <Bul. 27, Ga. St. Bd. Ent., pp. 76-78. 

Notes on experimental spraying with arsenical poison against plum curculio. 
Worsham, E. L.— Proceedings of the Twenty-first Annual Meeting of the 
American Association of Economic Entomologists. <Journ. Econ. Ent., vol. 
2 (1909), no. 3, pp. 207-208. 

Results of spraying with arsenate of lead against the plum curculio. 
Houghton, C. O.— Report on insects. <Trans. Pa. Hort. Soc. Del., vol. 22, 
pp. 42-43. 

1909. Taylor, E. P.— Spraying apples for curculio and codling moth.<Bul. 21, 

Mo. State Fruit Exp. Sta., pp. 11-18, 3 figs. 

Life history and habits of the plum curculio, and spraying experiments against 
same. 

1910. Scott, W. M., and Quaintance, A. L— Control of the brown rot and plum 

curculio on peaches.<Cir. 120, Bur. Ent., U. S. Dept. Agr. 

1910. Quaintance, A. L., et al.— The one-spray method in the control of the cod- 

ling moth and the plum curculio. <Bul. 80, Pt. VIII, Bur. Ent., IT. S. 
Dept. Agr. 

Gives results in experiments in control of plum curculio on apple. 

1911. Scott, W. M., and Quaintance, A. L— Spraying peaches for the control of 

the brown rot, scab, and curculio. <Farm. Bui. 440, TJ. S. Dept. Agr. 

Results of experimental and demonstration spraying of peaches for their several 
troubles in 1910. 

1911. Blake, M. A., and Farley, A. J.— Spraying experiments with peaches.<Bul 
236, N. J. Agr. Exp. Sta. 

Results of experiments in spraying peaches for brown rot, scab, and curculio. 
17262°— Bull. 103—12 16 



1909. 



1909. 



INDEX. 



Page. 

Acorn weevil. (See Balaninus victoriensis .) 

Ambrosia, host plant of stalk-borer, Triaspis curculionis reared therefrom 143 

Ampeloglypter sesostris, host of Myiophasia senea 149 

Anaphes conotracheli. (See Anaphoidea conotracheli.) 

Anaphoidea conotracheli, parasite of plum curculio 140-142 

Anisocyrta sp., parasite of plum curculio 148 

Anthonomus grandis, host of Myiophasia senea 149 

Triaspis curculionis 143 

quadrigibbus . (See Apple curculio.) 

scutellaris mistaken for plum curculio 28 

Antimony, black sulphid, against plum curculio 206 

Ants, enemies of plum curculio 152 

Apple, crab, food plant of plum curculio 33 

curculio mistaken for plum curculio 28 

results of sprays therefor 192 

spraying with arsenicals 201 

food plant of apple curculio (Anthonomus quadrigibbus) 28, 192, 201 

bud moth ( Tmetocera ocellana) 201 

cankerworms 201 

codling moth ( Carpocapsa pomonella) 201 

Enarmonia prunivora 201 

plum curculio 33 

tent caterpillar 201 

order of preference in oviposition by plum curculio 33 

scab, spraying with Bordeaux mixture or lime-sulphur 201 

spraying against plum curculio at Anderson, Mo 193-194 

St. Joseph, Mo 198-199 

Siloam Springs, Ark 196 

conclusions 200-201 

early experiments 189-193 

experiments by Bureau of Entomology 193-200 

in Virginia 197-198 

western New York and northwestern 

Pennsylvania 195 

scheme for orchards against plum curculio 201 

susceptibility of different varieties to plum curculio. 36 

worm, lesser. (See Enarmonia prunivora.) 

Apricot, food plant of plum curculio 33 

order of preference in oviposition by plum curculio 33 

Aramigus fulleri mistaken for plum curculio 29 

Arsenate of iron, paste, against plum curculio 188 

on peaches 206 

and self -boiled lime-sulphur against plum curculio. . . . 188 
powder, against plum curculio on peaches 206 

243 



244 THE PLUM CURCULID. 

Page. 

Arsenate of lead against apple curculio 192 

bud moth on apple 201 

plum curculio 185-189 

on apple 191-193, 196, 198, 199, 200 

peaches 203-215 

and Bordeaux mixture against apple insects 201 

plum curculio on apple 191-192, 

194-199 

lime-sulphur against apple insects 201 

water, injurious effects on peach 207 

self-boiled lime-sulphur against plum curculio. 188, 205, 211-216 

directions for using 213 

injury to peach variable 207 

powdered, against plum curculio 187 

Arsenicals (see also Poisons, etc.). 

against plum curculio on apple, early experiments 189-193 

experiments by Bureau of Ento- 
mology 193-200 

cherries and plums 215-218 

peaches 202-215 

plums and cherries 215-218 

spraying against plum curculio 178-185 

Arsenic sulphid against plum curculio on peaches 204, 206 

and self-boiled lime-sulphur against plum curculio on peaches. 206 

red, against plum curculio 186-188 

on peaches 206 

injurious effects on peach 207 

powder, and self-boiled lime-sulphur against plum cur- 
culio 188 

yellow, paste, against plum curculio 188 

and self-boiled lime-sulphur against plum cur- 
culio 188 

tersulphid against plum curculio 186-188 

on peaches 206 

injurious effects on peach 207 

powder, and self-boiled lime-sulphur against plum curcu- 
lio 188 

white, against plum curculio 181 

on apple 191 

and Bordeaux mixture against plum curculio on apple 191 

Arsenite of lime against apple curculio 192 

plum curculio on apple 191-192, 200 

and Bordeaux mixture against plum curculio on apple 191-192 

Arsenoid, green, against plum curculio on peaches 203 

injurious effects on peach 207 

Aspidoglossa subangularis, enemy of plum curculio 152-153 

Balaninus sp., host of Triaspis curculionis 143 

uniformis, host of Myiophasia senea 149 

victoriensis mistaken for plum curculio 29 

Barium carbonate against plum curculio ' 206 

sulphid against plum curculio 206 

Birds, enemies of plum curculio 154 

Black knot, breeding place of plum curculio 33 

of cherry and plum, use for egg laying and food purposes by plum 
curculio 37 



INDEX. 245 

Page. 
Bluestone, lime, and Paris green dust, homemade, against plum curculio on 

apple 194,200 

Boll weevil, cotton. (See Anthonomus grandis.) 

Bordeaux mixture against plum curculio on apple 196, 198 

and arsenate of lead against orchard insects 201 

plum curculio on apple 191-192, 

194-199 

arsenite of lime against plum curculio on apple 191-192 

Paris green against apple curculio 192 

plum curculio 183 

on apple 191-192, 194 

white arsenic against plum curculio on apple 191 

Bracon dorsata, parasite of plum curculio 148 

mellitor. (See Microbracon mellitor.) 

Bud moth on apple, spraying with arsenicals 201 

Calyptus tibiator, parasite of Myiophasia senea 149 

Cankerworms, spraying with arsenicals 201 

Carbonate of lead against plum curculio 206 

Chalcodermus seneus, host of Myiophasia senea 149 

sp., host of Myiophasia senea 149 

Chauliognathus pennsylvanicus, enemy of plum curculio 154 

Cherries, susceptibility of different varieties to attack by plum curculio 36-37 

Cherry, food plant of plum curculio 33 

order of preference in oviposition by plum curculio 33 

weevil, common name for plum curculio 14 

Cholomyia insequipes, parasite of Conotrachelus affinis 150 

elegans 150 

juglandis 150 

plum curculio 150-151 

synonyms 150 

Chrysopa larvae, enemies of plum curculio 152 

Commercial dust against plum curculio on apple 194-200 

Conotrachelus affinis, host of Cholomyia insequipes 150 

Triaspis curculionis 143 

elegans, host of Cholomyia insequipes 150 

Myiophasia senea 149 

Triaspis curculionis - 143 

gibbosus= Conotrachelus nenuphar 14 

juglandis, host of Cholomyia insequipes 150 

Metadexia basalis 150 

Triaspis curculionis 143 

nenuphar. (See Plum curculio.) 

variegatus= Conotrachelus nenuphar 14 

Copper sulpho-cyanid against plum curculio 206 

Crataegus, food plant of plum curculio 33 

Cryptorhynchus argula— Conotrachelus nenuphar 14, 16 

Cultivation for destruction of plum curculio pupae 176-178 

Curculio, common name for plum curculio 14 

nenuphar= Conotrachelus nenuphar 14 

original description 13-14 

origin of name 14-15 

persicse= Conotrachelus nenuphar 14 

plum. (See Plum curculio.) 



246 THE PLUM CUECULIO. 

Page. 

Currant, place of oviposition of plum curculio 33 

Diospyros virginiana. (See Persimmon, wild.) 

Dorymyrmex pyramicus, enemy of plum curculio. 152 

Eggplant, host plant of Trichobaris trinotata 143 

Enarmonia prunivora, larvae with those of plum curculio in black knot 142 

spraying with arsenicals • 201 

Epicxrus imbricatus mistaken for plum curculio 29 

Epiurus sp. (See Pimpla.) 

Eurytoma, parasite of plum curculio 148 

Evarthrus obsoletus, enemy of plum curculio 154 

orbatus, enemy of plum curculio • 154 

Ferrous arsenate against plum curculio 187 

powder, against plum curculio 188 

and self -boiled lime-sulphur against plum curculio. . 188 

Fowls, enemies of plum curculio 154 

Fruit curculio, common name for plum curculio 14 

Fruits, smooth-skinned, preferred for oviposition by plum curculio 33 

Gooseberry, place of oviposition by plum curculio 33 

Grape, larvae of plum curculio fail to mature therein 38 

place of oviposition by plum curculio 33 

Grosbeak, rose-breasted. (See Zamelodia ludoviciana.) 

Harpalus faunus, enemy of plum curculio 153-154 

pennsylvanicus, enemy of plum curculio 153-154 

Heliophila unipuncta, possible host of Myiophasia senea 149 

Hickory, host tree of Conotrachelus elegans 149 

Huckleberry, larvae of plum curculio fail to mature therein 38 

place of oviposition of plum curculio 33 

Hylocichla fuscescens, enemy of plum curculio ; 154 

g. pallasi, enemy of plum curculio 154 

Icterus galbula, enemy of plum curculio 154 

spurius, enemy of plum curculio 154 

Jarring against plum curculio. 168-176 

present status 172-176 

"Kerkelo," common name for plum curculio 14 

Lacewing fly larvae, enemies of plum curculio 152 

Lanivireo flavifrons, enemy of plum curculio 154 

Lead arsenate. (See Arsenate of lead.) 

oxid against plum curculio 206 

Lime against plum curculio on apple 189-190 

bluestone, and Paris green dust, homemade, against plum curculio on 

apple 194,200 

sulphur and arsenate of lead against apple insects 201 

self-boiled, and arsenate of lead against plum curculio on peaches. . 205, 

211-216 

arsenicals against plum curculio 187-188, 205-215 

directions for preparation 212 

Little Joker, common name for plum curculio 14 

Turk, common name for plum curculio 14 

London purple against plum curculio 182-185 

onapple 189-190 

peaches 202, 203 

Metadexia basalis, parasite of Conotrachelus juglandis 15° 

probably= Cholomyia insequipes 150 



INDEX. 247 

Page. 

Microbracon mellitor, parasite of plum curculio 148 

Musca longipes= Cholomyia inxquipes 150 

Myiophasia aenea, host of Calyptus tibiator 149 

parasite of Ampeloglypter sesost7-is 149 

Anthonomus grandis. ; 149 

Balaninus uni/ormis 149 

Chalcodermus seneus 149 

sp 149 

Conotrachelus elegans 149 

plum curculio 149-150 

Sphenophorus parvulus 149 

possible parasite of Heliophila unipuncta 149 

Nectarine, food plant of plum curculio 33 

order of preference in oviposition by plum curculio 33 

Nenuphar, common name for plum curculio 14 

Oriole, Baltimore. (See Icterus galbula.) 
orchard. (See Icterus spurius.) 

Paris green against apple curculio 192 

plum curculio 178-185 

on apple 189-192, 200 

peaches 202-207 

and Bordeaux mixture against apple curculio 192 

plum curculio 183 

on apple 191-192,194 

injurious effects on peach 207 

lime, and bluestone dust, homemade, against plum curculio on 

apple 194, 200 

Peach curculio, common name for plum curculio 14 

food plant of plum curculio 33 

order of preference in oviposition by plum curculio 33 

shoots, ovipositing place of plum curculio 38 

weevil, common name for plum curculio 14 

■worm, common name for plum curculio 14 

Peaches, spraying with arsenicals against plum curculio 202-215 

susceptibility of different varieties to plum curculio 36 

Pear, bark, ovipositing place of plum curculio, according to Fitch 38 

food plant of plum curculio 33 

larvae of plum curculio usually unable to mature therein 38-39 

order of preference in oviposition by plum curculio 33 

Pears, susceptibility of different varieties to plum curculio 38 

Pegomyafusciceps, association with plum curculio in fruit 151 

Persimmon, larva? of plum curculio fail to mature therein 38 

wild, place of oviposition by plum curculio 33 

Pimpla (Epiurus) sp., parasite of plum curculio 148 

Plowrightia morbosa. (See Black knot.) 

Plum curculio, adult (see also Plum curculio, beetles). 

activity in egg laying and feeding by day and night. . . 107-110 

choice of food 96-97 

description 33 

egg and feeding punctures, position on fruit and variation 

in form 103-106 

laying operation 99-102 



248 THE PLUM CTJKCTTLIO. 

Page. 

Plum curoulio, adult, extent of feeding of respective sexes 98-99 

period of emergence 92-95 

proportion of sexes 95-96 

relative number of feeding and egg punctures 106-107 

appearance of beetles in spring, relation of temperature thereto. 118-120 

time 112-118 

beetles (see also Plum curculio, adult). 

appearance in spring, relation of temperature thereto. . 118-120 

time 112-118 

from emergence to hibernation 127-129 

occurrence in orchards 120-125 

bibliography 219-241 

classification 13-14 

description 30-33 

distribution 19-27 

according to life zones 25 

egg and feeding punctures, position on fruit and variation in 

form 103-106 

relative number 106-107 

description 30 

laying and feeding activity by day and by night 107-110 

operation 99-102 

length of stage 48-54 

number deposited 39-48 

enemies, natural 139-154 

feeding and egg laying activity by day and by night 107-110 

punctures, position on fruit and variation in 

form 103-106 

relative number 106-107 

food plants 33-39 

fruit punctured or infested, percentage 134-139 

generations, number annually 125-127 

habits 39-112 

hibernation 129-132 

mortality during period 132-134 

history 15-19 

insects likely to be mistaken therefor 28-29 

introductions reported , 26 

larva, description 30-32 

habits of those just hatched and course taken in fruit — 54-55 

instars 55-56 

larvae, death in fruit 56-59 

fruits in which they fail to mature 38 

manner of leaving fruit and entering soil 64-65 

normal emergence from fruit during season 60-64 

undersized, desertion of fruit 59-60 

life history 39-112 

limit of occurrence, northern 24-25 

southern •. 25 

western 21-24 

losses due thereto 27-28 

mortality during hibernation 132-134 

names, common 14-15 



INDEX. 249 

Page. 

Plum curculio, natural enemies 139-154 

occurrence of beetles in orchards 120-125 

parasitic enemies 140-152 

percentage of fruit punctured or infested 134-139 

predaceous insect enemies 152-154 

pupa, description 32 

length of stage and time spent in soil, before and after 

pupation 83-87 

time spent in soil -/ 73-83 

pupa?, cultivation for destruction 176-178 

pupal cell, depth 87-88 

remedial measures 155-218 

historical 155-167 

remedies, cultivation for destruction of pupse 176-178 

jarring 1 68-176 

feeding experiments with poisons 185-189 

premiums therefor 167-168 

Ransom chip process 168 

spraying with arsenicals 178-185 

seasonal history 112-134 

spraying scheme for apple orchards 201 

of apple at Anderson, Mo 193-194 

St. Joseph, Mo 198-199 

Siloam Springs, Ark 196 

conclusions 200-201 

early experiments 189-193 

experiments by Bureau of Entomology 193-200 

in Virginia 197-198 

western New York and northwestern 

Pennsylvania 195 

peaches with arsenicals 202-215 

plums and cherries 215-218 

synonymy 13-14 

time for transformation from egg to adult 110-112 

of appearance of beetles in spring 112-120 

spent in fruit, egg and larval stages combined 65-73 

transformations in ground, effect of soil conditions thereon 88-92 

food plant of plum curculio 33 

gouger. (See Anthonomus scutellaris.) 
moth, so-called. (See Enarmonia prunivora.) 

order of preference in oviposition by plum curculio 33 

weevil, common name for plum curculio 14 

Plums, cultivated, variation in susceptibility to plum curculio 34-36 

Poisons (see also Arsenicals, etc.). 

against plum curculio, feeding experiments 185, 189 

Porizon conotracheli. (See Thersilochus conotracheli.) 
Potato-stalk weevil. (See Trichobaris trinotata.) 

Premiums for remedies for plum curculio 167-168 

Prunus americana, food plant of plum curculio 36 

angustifolia, food plant of plum curculio 36 

domestica, food plant of plum curculio 36 

hortulana, food plant of plum curculio 36 

simonii, apparently not injured by plum curculio 35 



250 THE PLUM CURCULIO. 



^J 
^ 



Page. 

Prunus triflora, food plant of plum curculio 35 

umbellata, food plant of plum curculio 36 

Quince, food plant of plum curculio 33 

order of preference in oviposition by plum curculio 33 

Ransom chip process against plum curculio i 168 

Rhynchxnus argula= Conotrachelus nenuphar 14 

cerasi— Conotrachelus nenuphar 14, 16 

Riparia riparia, enemy of plum curculio 154 

Rose-beetle, Fuller's. (See Aramigus fulleri.) 
Sigalphus curculionis. (See Triaspis curculionis.) 
Snout-beetle, imbricated. (See Epicserus imbricatus.) 

Soda, sulpho-arsenate, against plum curculio 188 

on peaches 206 

and self-boiled lime-sulphur against plum curculio 188 

injurious effects on peach 207 

Sphenophorus parvulus, host of Myiophasia senea 149 

Spraying with arsenicals against plum curculio 178-185 

on apple, early experiments. 189-193 
experiments by Bu- 
reau of Entomolo- 
gy 193-200 

cherries and plums 215-218 

peaches 202-215 

Strawberry, place of oviposition by plum curculio 33 

Swallow, bank. (See Riparia riparia.) 

Temperature, relation to time of appearance of plum curculio in spring 118-120 

Tent caterpillar, spraying with arsenicals 201 

Thelairodes basalis= Cholomyia insequipes 150 

Thersilochus conotracheli, parasite of plum curculio 147-148 

Thrips, enemy of plum curculio s 152 

Thrush, hermit. (See Hylocichla g. pallasi.) 
Tmetocera ocellana. (See Bud moth.) 

Toad, enemy of plum curculio 154 

Triaspis curculionis, parasite of Anthonomus grandis ". 143 

Balaninus sp 143 

Conotrachelus affinis 143 

elegans 143 

juglandis 143 

plum curculio 142-146 

stalk-borer on Ambrosia 143 

Trichobaris trinotata 143 

var. rufus, parasite of plum curculio 146-147 

Trichobaris trinotata, host of Triaspis curculionis 143 

on eggplant 143 

"Turk, " common name for plum curculio 14 

Veery. (See Hylocichla fuscescens.) 

Vireo, yellow- throated. (See Lanivireo jlavifrons.) 

Zamelodia ludoviciana, enemy of plum curculio 154 

Zinc cyanid against plum curculio 206 

oxid against plum curculio 206 

sulphid, injurious effects on peach 207 

o 



LE D '1.2 



